Discover the history of the 5th Foreign Regiment (5e RE), reactivated in Mayotte, Indian Ocean, in 2024. First organized in French Indochina in 1930, the “Regiment of Tonkin” maintained order there and was annihilated during the fighting against the Japanese in 1945. Recreated in 1949, it took part in the First Indochina War (1946-1954) against the Viet Minh. Therafter, the 5e Etranger participated in the conflict in Algeria, North Africa. Following that conflict, the unit was transferred to French Polynesia in the Pacific and became a combined Engineer-Legion regiment. It guarded and supported the French nuclear test site. The 5e RE was inactivated there in 2000. Read more in the following text…
Background: Foreign Legion in Indochina, 1883–1930
France’s interest in Southeast Asia dates back to the 1770s, when French volunteers began assisting Vietnamese Prince Nguyen Anh in his reconquest of all of Vietnam, which was achieved in 1802. The French later proclaimed a protectorate over Cambodia (1863) and occupied Vietnam’s southwestern provinces to create the colony of Cochinchina (1867). Their goal was to establish a profitable north-traveling overland trade route with China. However, the main obstacle was the Black Flag Army, a well-organized bandit force that operated in northern Vietnam (known as Tonkin back then) and controlled the local Red River, a lucrative trade route to the neighboring Chinese empire.
Initial clashes between the French (Major Rivière) and the Black Flag Army culminated in the Tonkin Campaign (1883-1886) and, later, the Sino-French War (1884-1885) with the Chinese. In fact, the latter had their own claims to suzerainty over Vietnam, seen as their sphere of influence. Therefore, China armed and supported the Black Flags and opposed French operations in Tonkin.
In late 1883, the Foreign Legion in Algeria (North Africa) was asked to reinforce the French expeditionary corps in Tonkin. The first legionnaires – the 1st Battalion under Major Doddier – landed in Vietnam on November 8. Later, another three battalions reinforced the French troops and succeeded in both campaigns, including famous battles at Son Tay, Bac Ninh, Lang Son, and Tuyen Quang.
In 1886, the French conquered Tonkin. A year later, in October 1887, French Indochina was formed. It comprised four protectorates: Cambodia, Cochinchina (Southern Vietnam), Annam (Central Vietnam), and Tonkin (Northern Vietnam). The Foreign Legion battalions remained in Tonkin and continued operations against local Vietnamese and Chinese bandits (called “pirates”) and guerrilla groups that often received hidden support from the Chinese authorities. In addition, the legionnaires built roads, bridges, outposts, barracks, and gardens. The official pacification of Tonkin was achieved ten years later, in 1896.
In the meantime, following the 1893 Franco-Siamese crisis with present-day Thailand, Laos was added to French Indochina.
From 1900 to 1907, a Foreign Legion operational regiment (a provisional unit) served in Tonkin. Thereafter, only two Legion battalions remained until 1915. Their men guarded the Chinese border, patrolled the region, and carried out infrastructure work. The situation changed upon the outbreak of World War I. In June 1915, the garrison was reduced to a single battalion. Ultimately, in 1916, only one autonomous company of the Legion was left to serve in Tonkin.
Following the end of the war, the French command decided to once again station four Legion battalions in Tonkin. They arrived there in 1920, 1922, 1927, and 1930. In the latter year, the four administratively independent, self-sustaining battalions (called Formant Corps, BFC) became a new Foreign Legion regiment.




5th Foreign Infantry Regiment from 1930 to 1940
In Hanoi, the capital of both Tonkin and all of French Indochina at the time, a four-week Foreign Legion Demi-Brigade (DBLE) was redesignated on September 1, 1930. The short-lived unit became the 5th Foreign Infantry Regiment (5e Régiment étranger d’infanterie, 5e REI), under Lieutenant Colonel Debas. The regiment, nicknamed the Regiment of Tonkin (Regiment du Tonkin), was composed of four battalions and headquartered in Viet Tri, northwest of Hanoi. However, it existed only on paper until April 1931.
The regiment was declared an overseas unit with rotated personnel, as were the previous BFC battalions. It comprised legionnaires who came in upon their own request from different Legion units in North Africa and rotated on a regular basis under a two-year individual stay assignment. The vast majority of Foreign Legion men considered Tonkin (and Indochina in general) to be a paradise compared to desert-filled North Africa, as Tonkin offered greenery, beautiful women, a moderate military regime, and a far better monthly salary. Therefore, usually, only legionnaires with several years of service and a completed deployment in Morocco (where pacification was going on until 1934) had a chance to see Indochina.
The tasks remained the same: guarding the border with China, maintaining order and conducting patrols in the region, and carrying out construction work.
5e REI’s composition in late 1930
- 1st Battalion (ex-4e BFC 1er REI; in Indochina from 1920)
- 2nd Battalion (ex-7e BFC 1er REI, ex-4e Btn/4e REI; from 1927)
- 3rd Battalion (ex-9e BFC 1er REI, ex-4e BFC/2e REI; from 1922)
- 4th Battalion (ex-1er BFC 1er REI; from 1930)
In late 1930, one of the battalions deployed to Annam to suppress a local rebellion. It stayed there for two years.
In May 1932, the 5e REI received its regimental colors. In September, the 4th Battalion became a new 3rd, which was disbanded at the same time.
In the late 1930s, the 5e REI men in Tonkin built hundreds of miles of roads through the jungle.
In September 1939, World War II broke out in Europe. The regiment was tasked with building fortifications. In June 1940, following Germany’s victory in the six-week Battle of France, the French were forced to sign an armistice. This resulted in a partial German occupation of France and the establishment of a new French (Vichy) government that adopted a policy of collaboration.
To make matters worse, the Japanese, who were allies of Germany, entered Tonkin and occupied Lang Son, Vietnam’s gateway to China, in late September 1940. During the occupation, minor clashes occurred between the invaders and the 2nd Battalion 5e REI units, stationed in the town. However, negotiations between the French and Japanese authorities prevented a certain bloody confrontation. On September 25, an agreement was reached with Japan. As a result, about 40,000 Japanese troops could be deployed across French Indochina.
In October, the first clashes took place with Vietnamese rebels who opposed both the French and the Japanese occupation. Among their main forces was a certain Viet Minh. Later that month, the 1st Battalion moved to Cambodia, another part of French Indochina, to defend the border against Thailand. At the same time, the 3rd Battalion restored order in Cochinchina. Later, the unit also moved to Cambodia.
Between November 1940 and mid-January 1941, the 2nd Battalion took part in operations to restore order in poorly accessible mountainous areas of northern Tonkin.
In late 1940, the 5e REI was led by Lieutenant Colonel de Cadoudal and consisted of 47 officers, 171 NCOs, and 1,777 legionnaires. About 1,150 local auxiliaries were also assigned to the regiment, from late 1939.






5th Foreign Infantry Regiment from 1941 to 1945
In January 1941, a new conflict began in French Indochina: the Franco-Thai War. From October 1940, Thailand (which later that year sided with Japan and declared war on the U.S.) wanted to regain some of the former vassal state territories in French Indochina’s Cambodia and Laos that it had lost from the 1860s to the 1900s. Border skirmishes and air attacks took place. In early January 1941, the well-equipped Thai army attacked and occupied Laos.
In Cambodia, the French forces, including two 5e REI battalions (1st and 3rd), offered more resistance. The men from the 3rd Battalion distinguished themselves on January 16, during the Battle of Phum-Preav, the fiercest battle of the war. They faced an enemy using modern tanks and armored vehicles supported by attack aircraft. Yet the legionnaires still managed to stop the Thai column. In the eight-hour battle, the regiment suffered the losses of Captain Chalvidan, Lieutenant de Cros Peronard (an officer of Danish origin), and 33 legionnaires. Many more were wounded. For that action, the battalion earned the highest possible citation, at the Army level.
A ceasefire was signed on January 28. The war formally ended with a peace treaty on May 9, 1941.
In late July 1941, Japanese troops invaded southern French Indochina and, thus, occupied the entire territory. French authorities and soldiers were allowed to remain, although they were under Japanese surveillance.
The geopolitical situation deteriorated at the same time. The British now considered the French, their allies until the fall of France, to be an enemy. They invaded and occupied the French-controlled Levant in the Middle East and tried to invade other French colonial territories as well. To support their actions, the British created a naval blockade and denied the French contact with Indochina. This meant that from late 1941, none of the 5e REI men could leave the regiment and be shipped back to Africa, nor could the regiment receive new reinforcements and supplies.
From that moment on, the 5e REI – now under Colonel Alessandri from the colonial troops – lived its own relatively calm life as an autonomous unit without contact with the Legion headquarters in Algeria. Routine daily duties alternated with occasional exercises and sports competitions. Officers took turns teaching at the local military academy.



5e REI and the Japanese coup d’état in 1945
With the Allied invasion of France in 1944 and the following liberation of the country, the Japanese were concerned about a possible uprising against them by French colonial forces. That’s why, on March 9, 1945, they attacked French garrisons all over the colony in what is known as the Japanese coup d’état in French Indochina. The badly equipped garrisons were overrun. In the meantime, the Japanese replaced French administration authorities and created new puppet states: the empire of Vietnam, the Kingdom of Cambodia, and the Kingdom of Laos. French Indochina formally ceased to exist.
The coup d’état was very sad and bloody for the 5e REI. Lieutenant Colonel Belloc, who had commanded the regiment since late 1942, was arrested by the Japanese in Viet Tri, the unit’s headquarters. His staff officers were also arrested. Major Laroire, head of the staff, was seriously wounded and died. As a captain, he commanded a company during the famous 1941 Battle of Phum-Preav.
In Lang Son, the Tank Platoon of the 5e REI’s Motorized Detachment (DML) defended the French garrison. Led by Lieutenant Duronsoy, the legionnaires fought for 18 hours. Ultimately, the Japanese executed the survivors.
In Ha Giang, the Disciplinary Platoon (Section Speciale de Discipline), consisting of 87 men under Adjudant-chef Sury, fought all night. Eighty-two legionnaires were massacred afterward.
In Hanoi, the Motorized Detachment’s commander, Captain Fenautrigues, was killed while asking the Japanese what was going on. His unit was defending the Citadel of Hanoi: the Armored Platoon under Adjudant Roman with four armored cars (Panhard Levassor) and the Moto Platoon under Adjudant Lacroix-a-Grandpierre with four motorcycle groups. The DML detachment fought for over 15 hours. Twelve legionnaires were killed, and another 20 were wounded.
In Vinh (central Vietnam), the Anti-Aircraft Detachment (DCA), comprising 16 legionnaires under Sergeant Faussonne, fought bravely and was annihilated.
Near Mount Bavi (northern Tonkin), where a regimental holiday center was based, the 7th Company 2nd Battalion was involved in a fierce battle with the Japanese. Only 30 legionnaires survived. Later, they successfully rejoined their battalion.
In Tong, the 1st and 2nd Battalions under Captains Gaucher and De Cockborne joined a French column formed by their former colonel, now-General Alessandri. He had assumed command of the Western Red River Group in 1943. Alessandri grouped the remaining French forces stationed in the region (about 1,500 troops) and led them on a fighting retreat 500 miles (800 km) toward Chinese territory. The 3rd Battalion under Captain Lenoir joined them the next day after it had participated in heavy fights at Tien Kien. There, it lost one of its officers: Second Lieutenant Herbert Muller, a long-serving legionnaire of German origin, aged 46.
The battalion’s 9th Company, under Captain Chaminadas, operated fully independently. It was cut off from the rest of the regiment and marched to China alone.
In Tong on March 10, the Japanese fatally wounded Lieutenant Colonel Marcelin, commander of the Tong-Sontay sector. He died the next day. Along with him, two officers and 25 legionnaires were killed.
Two days later, on March 13, General Alessandri’s column was reorganized. The French had to march 500 miles (800 km) toward China through the jungle. Being poorly clothed, poorly supplied, and poorly equipped, the men were decimated by hunger, fatigue, and disease. They were also chased by the Japanese and got involved in several fierce battles at Ba Na Ghna, Son La, Muong Yo, and Mali Tao, where 12 legionnaires were killed and Captain de Cockborne wounded.
After an exhausting 52-day march, Alessandri’s column crossed the Chinese border on May 1. They would have to travel another 300 miles (about 450 km) before they reached Tsao Pa, a site where French troops concentrated after retreating from Tonkin. They arrived on June 15 after having traveled about 800 miles (1,250 km) in 93 days.
On June 30, 1945, the 5e REI was inactivated in Tsao Pa, South China.




5e REI provisional units from 1945 to 1946
In China’s Tsao Pa, on July 1, 1945, the Provisional Battalion 5e REI (Bataillon de Marche du 5e REI, BM5) was created under now-Major Gaucher, former commander of the 1st Battalion. The BM5 comprised about 30 officers and 580 legionnaires who had survived the long march from Tonkin. They formed an HQ company, three combat companies (1st, 2nd, and 3rd), and a depot company.
A few days later, the 9th Company of the 3rd Battalion, accompanied by other 5e REI elements, reinforced the BM5. They came to China another way, on their own.
At the Potsdam conference in July 1945, the Western Allies divided Indochina into two zones, attaching the southern zone to the British and the northern part to Chiang Kai-shek’s China to accept Japan’s upcoming surrender.
In late August, after the Japanese announced their capitulation, Vietnamese nationalists’ Viet Minh movement, under Communist Party leader Ho Chi Minh, organized a general insurrection and seized power from the very weak pro-Japanese government of the Empire of Vietnam. They proclaimed the independence of their Democratic Republic of Vietnam on September 2, the same day World War II ended with Japan’s official surrender.
In the meantime, on August 20, Chiang Kai-shek’s Chinese forces crossed into northern Vietnam. Unlike the British in the south, they refused an immediate French return and supported Ho Chi Minh’s Viet Minh, allowing him to proclaim the republic.
In mid-September, the first British forces arrived in Saigon in southern Vietnam (Cochinchina). They were accompanied by the first detachment of French troops. Along with the remaining Japanese units, the joint British/French/Japanese armed patrols helped France regain control over Indochina. In late September, when the French officially declared their authority restored in Cochinchina, the Viet Minh (and other minor anti-French armed groups) launched a guerrilla war, which soon spread to the north as well.
At the same time, French soldiers whom the Japanese had imprisoned in March were released and formed new units. This was also the case with the 5e REI legionnaires imprisoned in Tonkin.
Regrouped in Hanoi, along with wounded and hospitalized comrades who hadn’t made it to China, they formed the Autonomous Battalion 5e REI (Bataillon de Formant Corps du 5e REI, BFC5) on October 13, 1945. Major Dumaine from the colonial troops took command, with Captain Besset as his deputy. The latter officer had participated in the long and exhausting march to China with the 2nd Battalion 5e REI and led it temporarily after Captain de Cockborne was badly wounded during the last fights with the Japanese. The BFC5 was the first Foreign Legion unit to be present in French Indochina after the end of World War II. In early 1946, the battalion left Hanoi and was transferred to Saigon. It participated in military operations against Viet Minh rebels in Cochinchina alongside legionnaires from the 13e DBLE.
In mid-February 1946, the other battalion comprising former 5e REI men – BM5 – arrived in Tonkin, which the Chinese still occupied. The BM5 was not allowed to enter the previous 5e REI garrisons. Its units had to live in the jungle. In the meantime, clashes with the Viet Minh started. In early March, 18 rebels were killed at Tuan Giao.
From April to September, the BM5 served in northern Laos, where its men became involved in numerous clashes with the rebels. They also built fortified outposts and conducted patrols. From June, they served in the Xam Neua region.
In late October 1946, both 5e REI battalions were regrouped in Saigon and disbanded, with their men waiting for repatriation.
On December 12, the 5e REI survivors boarded a ship and returned to North Africa after many years. They arrived in Sidi Bel Abbes, the Legion’s HQ, on January 20, 1947, and received a warm welcome. Their long, poignant odyssey was over, as was the history of the original 5th Foreign Regiment.




5th Foreign Infantry Regiment from 1949 to 1950
In December 1946, a regular conflict broke out between the French and the Viet Minh: the First Indochina War. One by one, Legion units arrived in Southeast Asia to reinforce the French troops involved in the war. This was also the case with two battalions that landed in Tonkin in July 1949: the 3rd Battalion 6e REI from Tunisia and the 5th Battalion 4e REI from Morocco. They operated in Tonkin until October, when an order to form a new Foreign Legion regiment arrived.
On November 1, 1949, a new 5th Foreign Infantry Regiment was reactivated with the two North African battalions. The 6e REI unit became the 1st Battalion 5e REI, while the 4e REI unit became the 2nd Battalion 5e REI. Each battalion comprised a small HQ, an HQ company, and four combat companies.
The new 5e REI’s HQ was stationed in Haiphong, east of Hanoi. The 1st Battalion was garrisoned in Son Tay and the 2nd in Tien Yen. Lieutenant Colonel Binoche, a Legion officer who had lost his right arm in World War II, took command of the regiment.
The 5e REI men conducted operations in the Hoa Binh, Haiphong, and Phu Ly regions.
Near Ninh Giang, on March 6, 1950, the 1st Battalion killed about 250 Viet Minh men and captured 37 during Operation Tonneau.
In early April, the 3rd Battalion was constituted at Hongay (now Ha Long), northeast of Haiphong, mainly with Vietnamese auxiliaries.
Two weeks later, on April 12, 1950, in Haiphong, the 5e REI received its new flag from General Alessandri, the former commanding officer of the original regiment, who headed its surviving elements to China. He now served as the Chief of the French ground forces in Tonkin.
Meanwhile, all three battalions deployed to the coast of the South China Sea, between Haiphong and the Chinese border, to occupy local outposts. They also participated in Operation Parpaing in the Dong Trieu massif alongside the 3e REI.
In June, the 2nd Battalion served at That Khe in the north, on Colonial Road 4 (RC4). The 1st Battalion operated northwest of Phu Ly, south of Hanoi. On July 7, its commander, Captain Darès, died during an operation. An officer of Senegalese origin and a World War II veteran, he was probably the only native Black African who ever commanded an operational battalion of the Legion.
In mid-July, the 1st Battalion was transferred to Tourane in Annam (Central Vietnam) and took part in operations near Quang Nam. It returned to Tonkin in September and was posted to Mon Cay and Tien Yen.
At the same time, the Battle of Colonial Road 4 began. Viet Minh troops launched an offensive that forced the French, including the 3e REI, to retreat from the Cao Bang and That Khe regions bordering China. The 2nd Battalion protected withdrawing columns near Na Cham, on RC4. It returned to Tien Yen in early November. At the same time, the 3rd Battalion reinforced the 1st at Mon Cay, where Viet Minh activity had increased in recent weeks.
In December, a French combined arms task force – Mobile Group 6 (GM6) – was formed. It included the 2nd and 3rd Battalions. They operated northwest of Tien Yen, around Dinh Lap and Binh Lieu. The 2nd Battalion suffered about 50 men killed and wounded.
5th Foreign Infantry Regiment in 1951
In January, the 2nd Battalion was back in Tien Yen. The unit carried out construction work, patrols, and operations in the region until mid-1952.
The 1st Battalion left Mon Cay and was transferred to Viet Tri on the Red River – once the HQ of the original 5e REI – in late February. Its men participated in the construction of the De Lattre Line. This was a defensive line in Tonkin’s Red River Delta, named after General de Lattre de Tassigny, then-commander-in-chief in Indochina. It comprised concrete fortifications, obstacles, and weapons installations.
In the spring, the 3rd Battalion (minus the 11th Company) left Mon Cay and moved to Sontay, northwest of Hanoi. It took part in building the De Lattre Line alongside the 3rd Battalion 2e REI.
On March 1, the 4th Battalion 5e REI was activated in Hongay. The vast majority of members were Vietnamese auxiliaries, with Legion cadres. This was known as the “yellowing” (jaunissement) of the French forces in Indochina to replenish the depleted units with local volunteers. The battalion patrolled the region and protected local coal mines.
In May, the 1st Battalion moved to Dong Trieu, on Provincial Road 18 (RP18). It continued constructing the De Lattre Line and conducting patrols. During one of these patrols, on July 14, a platoon of its 3rd Company was ambushed. Out of 18 legionnaires under Sergeant Werner, only one survived.
On August 27, the 3rd Battalion took part in a major battle near Ap Da Chong, close to the Black River. Shortly afterward, it was incorporated into GM4 and operated between Hung Yen and Thai Binh, in the Red River Delta. In early October, the battalion suffered heavy casualties during Operation Mandarine near Noi Thon. However, the Viet Minh also suffered a loss: hundreds of men killed, wounded, or imprisoned. The battalion returned to Hanoi and earned a citation at the Army level.
From November 1951 until February 1952, the 1st and 3rd Battalions fought in the Battle of Hoa Binh, west of Hanoi, and occupied the city. On December 16, the 1st Company was heavily attacked west of Hoa Binh on Colonial Road 6. Four legionnaires were killed, while 57 were injured or went missing.

5th Foreign Infantry Regiment in 1952
Unfortunately, Hoa Binh had to be supplied almost exclusively by airdrop, as the Viet Minh repeatedly interrupted the connection via RC6. Thus, in late February 1952, the French command decided to abandon the town. The two 5e REI battalions protected the French retreat and suffered several killed and wounded.
The 1st Battalion was transferred to the south of the Red River Delta, near Nam Dinh. On April 6, about 200 Viet Minh men were killed during Operation Mercury. On April 18-19, the battalion fought at Dai Vi Thuong; hundreds of Viet Minh soldiers were killed or captured. However, the Legion losses were also very high: Three lieutenants and 36 legionnaires were killed, and 105 legionnaires were wounded. For these actions, the battalion received the Foreign Theaters of Operations’ War Cross with a citation at the Army level. In May, the battalion moved to Bac Ninh, northeast of Hanoi.
After leaving Hoa Bonh, the 3rd Battalion was ordered to patrol RC5, east of Hanoi. There, on May 18, at Tho Lao near Ke Sat, it took part in Operation Dromedaire, which cost the Viet Minh 90 dead and 78 imprisoned.
In June, the battalion left Tonkin for Quang Khe in Annam. Then, it moved to the Tourane region, where it participated, until September, in operations against the Viet Minh’s Regiment 101 alongside legionnaires from the 1er REC and the 13e DBLE.
In the meantime, in mid-June, the 4th Battalion left Hongay and was transferred to Bac Ninh to patrol local main roads.
In late July, after 18 months, the 2nd Battalion left Tien Yen. It was posted in the Phat Diem region south of the Red River Delta.
In October, the 3rd Battalion deployed to the valley of Na San in western Tonkin to build a fortified camp in the path of the advancing enemy. The camp consisted of numerous defensive positions.
To support the camp’s French garrison, a new unit was formed within the 5e REI: the Foreign Legion Mortar Company (CMLE), activated on November 1, 1952.
Both 5e REI units helped defend the valley during the Battle of Na San in late November. Three Viet Minh divisions suffered up to 3,000 men killed and wounded; they were forced to stop the offensive and withdraw. The 3rd Battalion distinguished itself and earned a new citation at the Army level.
In late December, the 1st Battalion replaced the 2nd in the Phat Diem region. The replaced battalion moved to Bac Ninh.

5th Foreign Infantry Regiment in 1953
On February 28, 1953, the 4th Battalion 5e REI, comprising Vietnamese auxiliaries, was formally deactivated. The next day, it became the 75th Vietnamese Battalion (75e BVN or Tieu Doan 75) of the pro-French Vietnamese National Army.
The 2nd Battalion in the Bac Ninh region fought a remarkable battle at An Tu on March 1. The enemy’s Regiment 238 suffered 37 killed and 52 imprisoned.
In late April, the 3rd Battalion left Na San and was transferred to Luang Prabang in Laos. It returned to Tonkin in late May to operate in the delta.
At Na San, on June 1, the CMLE was redesignated and became the 2nd Foreign Legion Mortar Mixed Company (2e CMMLE).
In mid-June, GM5 was constituted; it included the 2nd and 3rd Battalions 5e REI. The group participated in Operation Hirondelle on RC4 in mid-July.
At the same time, the 1st Battalion under Major Masselot received the fourragère (shoulder cord) in the colors of the Foreign Theaters of Operations’ War Cross (TOE, blue/red) for the two citations that the battalion had earned.
In late August, the battalion moved from Phat Diem, a little northwest, to Ninh Binh, while the 2e CMMLE left Na San for Bac Ninh.
From September to October, GM5 took part in Operation Brochet in the delta. The battalions suffered 27 dead and 159 wounded, while the Viet Minh suffered 172 killed and 230 wounded. The 2nd Battalion subsequently moved to Dinh Bang, between Hanoi and Bac Ninh.
From October to November, the 1st Battalion participated in Operation Mouette south of the Red River Delta, along the 3rd Battalion 13e DBLE, opposing the enemy Division 320. During the night of October 22-23, 1953, the 5e REI battalion was attacked at Chi Phuong. It suffered five dead and 25 wounded. On November 2, near Phu Nho Quan on RP59, the battalion once again faced a strong Viet Minh force; it suffered six dead, 25 wounded, and 49 missing.
In mid-November, the unit was transferred to Yen Cu Ha on the Day River, which flows through Hanoi and Ninh Bình to the Gulf of Tonkin. It remained there until late December.
Meanwhile, GM5 was stationed at Nam Dinh. In December, the last Vietnamese auxiliaries left the 3rd Battalion. They had been replaced by ordinary legionnaires.

5th Foreign Infantry Regiment from 1954 to 1956
In early January 1954, the 1st Battalion was sent to Laos to advance in the direction of Thakhek, a town in the south-central part of the country. On January 31, it was attacked at Ban Poung; 86 Viet Minh soldiers were killed.
Starting in January, the 3rd Battalion carried out operations in the Thai Binh region, in the Red River Delta. The operations lasted until mid-February. At Thuong Thon on January 24, 68 Viet Minh men were killed and 94 were captured.
In Nam Ninh on February 17, Lieutenant-Colonel Raberin, then-head of the 5e REI, awarded the 3rd Battalion with the fourragère in the colors of the Foreign Theaters of Operations’ War Cross for the two citations it had earned.
From late February, the battalion, along with the 2nd, participated in operations in the Ninh Binh region, still as part of GM5. They engaged in a fierce battle at Trung Thon on March 2. Together, they suffered 182 men killed, wounded, or missing.
In western Tonkin, the Battle of Dien Bien Phu began in mid-March. The 2e CMMLE, deployed there from late December 1953, participated.
In Laos, a large number of Viet Minh troops attacked the 1st Battalion at Ban Sa Angon on March 22. The battalion suffered 48 dead, including Lieutenant Vaugrente, and 125 wounded, including the battalion commander, Major de Buretel De Chassey. The latter succumbed to his injuries several days later.
On the night of April 7-8, the 3rd Battalion fought at Quong Kien. It suffered 29 men killed, 68 wounded, and 12 missing. The Viet Minh had about 250 dead or wounded.
Another bloody battle took place at Vinh Truyen on April 16. This time, both 5e REI battalions of GM5 participated. There were 18 dead and 72 wounded on the Legion side, while the Viet Minh lost about 150 men. However, the losses for the 5e REI were very high. Thus, the battalions had to temporarily merge into a single operational battalion. In late April, they left Nam Dinh and moved to Hanoi.
In early May, the decisive Battle of Dien Bien Phu was over. All participating units were annihilated. This included the 2e CMMLE, which was officially disbanded on May 31.
From May, the entire 5e REI was posted on RC5, between Hanoi and Haiphong, to protect the road. Many understood that the lost battle at Dien Bien Phu would lead to the end of the war, and they were correct. On July 27, an armistice went into force in Tonkin. Within two weeks, the conflict in French Indochina was over.
During the First Indochina War, the regiment lost 22 officers and 654 NCOS and legionnaires.
In late July, the 5e REI battalions returned to Hanoi. However, they had to leave the city on October 9, 1954, when the Viet Minh officially occupied it. The 5e REI legionnaires were the last French troops to leave the former capital of Indochina, offering a reminder of the old glory of the original “Regiment of Tonkin.”
The 5e REI moved first to Kien An near Haiphong and then to Tourane in Central Annam, where the battalions arrived in early November. They would carry out patrols, exercises, maneuvers, and construction work.
In March 1955, a new Camp de Chassey was finished near Tourane. In early June, the 3rd Battalion left the city for Saigon in Cochinchina. It was followed by the 2nd in mid-July and the 1st in September. They were stationed south of the capital.
However, Indochina had already been lost for France. Therefore, on January 14, 1956, the 1st and 3rd Battalions of the 5e REI left it for North Africa along with the 1er REC.
As for the 2nd Battalion, on March 15, 1956, it became the last Foreign Legion battalion to leave Southeast Asia. Three weeks later, in early April, it landed in Algeria.






5th Foreign Infantry Regiment from 1956 to 1957
Since the end of the conflict in Indochina, the situation had deteriorated considerably in French North Africa. In late 1954, local rebels began carrying out hostilities in Morocco, Tunisia, and Algeria. In the latter country, the anti-French insurgency was represented mostly by the National Liberation Front (FLN) and its armed branch, the ALN. The rebels engaged in guerrilla warfare and attacked the French representatives (both indigenous and European) and French military convoys, depots, and smaller posts. In addition, they raided pro-French indigenous communities and French-owned plants and farms. During these raids, as a warning, they killed the innocent civilians living or working there. In response, the French authorities launched anti-insurgent policy and military operations across Algeria, although they had never officially declared war.
A month after the first two 5e REI battalions landed in North Africa in early February 1956, Morocco and Tunisia became independent. Thus, all French efforts were directed solely at restoring order in the country that had been the home of the Foreign Legion since 1831: Algeria.
The 5e REI under Lieutenant Colonel Andolenko was, for the first time, stationed outside Asia. Its men were initially based at Orleansville (now Chlef) in the north of the country. Then, the 1st Battalion moved to Nedroma and the 3rd to Marnia, both in the Tlemcen region, on the border with Morocco. The first fight took place there on March 20. That day, Captain Cozette became the first 5e REI man killed in action in Africa.
In early April, the 2nd Battalion landed in Algeria. It was posted near Ain Temouchent, between Tlemcen and Sidi Bel Abbes, the Legion’s HQ. The same month, the other battalions participated in fierce battles during which over 100 rebels were killed. For the rest of the year, the regiment operated in the Tlemcen region of the Oran department. The exception was the 3rd Battalion under Major Chenel, a veteran of the fights against the Japanese with the original 5e REI. His unit deployed to the east of Oran, between Frenda and Relizane, from September to early November.
Most of the 5e REI’s operations took place at Djebel Fillaoussene, a mountain close to the Moroccan border northwest of Tlemcen. Helicopters became a popular means of transporting legionnaires into the heart of enemy territory. The Piasecki H-21 “Banana” remains an iconic part of the Algerian War.
In June, the 3rd Battalion was transferred to Tlemcen, while the 1st was posted southwest of that town, to Hafir, in July. The same month, the 2nd Battalion – now minus the disbanded 7th Company – moved east of Tlemcen, to Turenne (now Sabra). In November, the regiment’s HQ – augmented by a dog platoon – was also based in this small town. For the record, the Turenne Rail Accident, which caused the deaths of 56 legionnaires, had occurred near the town in late 1932.
The regiment’s last important action of the year took place on December 6. That day, the 8th Company, along with the 3rd Battalion, pursued an enemy detachment at Djebel Tefatisset, a mountain east of Tlemcen. At least 38 rebels were killed.
That year, the 5e REI killed, wounded, or captured 744 rebels and suffered 50 dead.
In 1957, the regiment operated primarily in the Turenne sector. Its colonel was the sector’s military commander. Three main missions were carried out there: defeating rebels in the sector, protecting means of communication and the Beni Badhel dam (which distributed drinking water to the city of Oran), and supporting the local population. The 5e REI legionnaires also became a rapid reaction element of West Oran. In addition, they conducted patrols, carried out construction work, and engaged in convoy protection.
Important clashes occurred throughout the year. In mid-January, 23 rebels were killed at Douar Kreane; January 26 marked the most successful day, when 92 rebels were eliminated at Djerf El Bellel; 28 rebels died at Djebel Nekrif in mid-February; at Djebel Fillaoussene, the enemy lost 73 men on April 20; over 50 rebels were killed in May, as well as at Sidi Mammar on June 13; and at Dar Cheikh on October 16, the 11th Company eliminated 25 rebels.
In mid-1957, the already reduced 2nd Battalion was disbanded, and the 1st moved from Hafir to Turenne.
In December, following the rule prescribed for all Legion infantry and cavalry regiments, a Harka was activated within the 5e REI. This auxiliary group, usually mounted on horseback, comprised local pro-French Muslim Arabs called harkis and commanded by Legion cadres.
That year, 540 rebels were killed and 109 imprisoned by the regiment.







5th Foreign Infantry Regiment from 1958 to 1960
Until late March 1958, operations continued in West Oran. These included fights at Tleta, Bouchouk, and Djebel El Gorine. On April 20, the regiment’s monumental war memorial was unveiled in the cemetery of Tlemcen.
From early May to late July, the 1st Battalion deployed to the Djelfa region in the central part of Algeria, at the foot of the Saharan Atlas mountain range. There, at Djebel Bou Kahil on July 27, the battalion lost eight men, including Lieutenant de Longueau Saint Michel, while eliminating 40 rebels.
In early October, the 5e REI – now under Colonel Favreau, a World War II veteran who had lost his right eye in combat with the Germans – was reorganized and transformed into an intervention force. Its two battalions were disbanded and replaced by two more flexible EMT operational elements which consisted of a small HQ and three companies. Meanwhile, the 4th Company became a Motorized Company equipped with U.S. Dodge WC trucks, and the 10th was transformed into a Combat Support Company equipped with mortars. Now, the new regiment was available at all hours, capable of all missions, and free from all sector constraints.
The rest of the year was spent carrying out operations across Oran and finishing them near Figuig and Ain Sefra, close to the Moroccan border. In late December, the 5e REI was stationed about 120 miles (190 km) northeast of Turenne, in the port city of Arzew, where its men would build a new large camp and rear base.
From early February to early April 1959, the 5e REI deployed about 150 miles (some 250 km) east to the Ouarsenis mountain range, where one heliborne operation followed another. The enemy lost 63 men killed and 36 captured. After a short stay in Arzew came a new deployment to the Ouarsenis, this time with 95 rebels killed and 34 imprisoned. However, in May, the regiment lost Lieutenant Ivanoff, Adjudant-Chef Valko, and nine legionnaires. In late June, the men were back in Arzew.
At the time, the dog platoon was no longer active within the regiment.
In July, the 5e REI participated in Operation Etincelle in the Hodna Mountains (part of the Saharan Atlas), then Operation Jumelles. There followed operations in the mountainous and forested region called Grande Kabylie (Great Kabylia), starting in early August. On October 8, EMT1 eliminated 36 rebels and took seven prisoners. A week later, the regiment was back in Arzew. In early November, it deployed all the way to the other side of the country, the Collo peninsula near the Tunisian border, a region with difficult, forested terrain, and harsh climate. Apart from a short trip to the capital of Algiers, the year 1960 was to run until October in the peninsula. The 5e REI men, now wearing a camouflage uniform and a green beret, operated close to the 3e REI and the 13e DBLE. However, the enemy had suffered such a heavy blow in previous operations that its survivors went into hiding, and clashes became very rare.
In October 1960, the regiment moved to the Aures mountains, east of the Hodna. This was an inhospitable region that had been heavily affected by the insurgency since the beginning of the conflict. With a short stay back in Arzew, the regiment remained there until late December. Then, it moved to guard the Algeria-Tunisia border until mid-February 1961.




5th Foreign Infantry Regiment from 1961 to 1963
Back in Arzew, minor operations in the city of Oran and on the Algeria-Morocco border followed.
In mid-March, the regiment deployed some 220 miles (350 km) southeast to Geryville (now El Bayadh). In May, it moved to the Morice Line, a fenced, barbed-wired, electrified, mined, and constantly monitored defensive line running along the border between Algeria and Morocco. The order was given to neutralize all rebel groups willing to cross it. The companies were carrying out day and night patrols along the line, protecting the electro-mechanical technicians and clearing the snow-covered electrified networks. The military situation had changed, however, and the rebels were becoming rarer sights.
Finally, on March 19, 1962, the Évian Accords treaty ended the Algerian War. In early July, France recognized Algeria’s independence.
During the Algerian conflict, the 5e REI had seen 146 officers, non-commissioned officers, and legionnaires killed and 353 wounded.
Now the legionnaires were busy setting up posts, carrying out the inevitable reconnaissance, guarding convoys, guarding units of all kinds, and keeping their units in shape through raids, shootouts, combat training, and team sports, so as not to be discouraged by the end of hostilities on the one hand and by the uncertainty of the regiment’s future on the other.
In October 1962, the 5e REI was stationed in Ain Sefra, replacing there the 2e REI. In the meantime, France’s loss of Algeria led to the reorganization and significant reduction of the French armed forces, including the Legion. Fears of the regiment’s dissolution were eventually quelled, and in March 1963, newly appointed Lieutenant Colonel Nouguès could report Paris’ final decision to move the unit to French Polynesia in the Pacific. (The initially planned New Caledonia was rejected.)
The newly reorganized regiment was to be of the military engineering type. Specialist training courses in the operation and maintenance of various types of heavy equipment were therefore held in mainland France (Montpellier and Grenoble), while others took place at the (still functioning) Arzew rear base, organized by instructors from the Engineer Corps.
In late June, the first 5e REI legionnaires left Algeria for Tahiti in French Polynesia. They landed there on July 19. Some of them began to build a military base in Arue, suburbs of Papeete (the capital city of French Polynesia located on Tahiti), while others moved to Moruroa, an atoll chosen for France’s new nuclear test site.
In September, another 120 legionnaires left Algeria for Tahiti. The next month, these detachments in French Polynesia created the nucleus of a new 5th Regiment.
In the meantime, the original 5e REI regrouped in Arzew under Major Desjeux. The considerably reduced unit consisted of the HQ Company and the 2nd Company. Following a period of eight weeks, during which the two regiments were in a state of coexistence, the original 5e REI was officially disbanded on November 30, 1963.






5th Pacific Mixed Regiment from 1963 to 1984
In Tahiti, French Polynesia, the 5th Pacific Mixed Regiment (5e Régiment Mixte du Pacifique, 5e RMP) was activated on October 1, 1963. A combined engineering unit, it was composed of former 5e REI legionnaires, regular Army sappers, and marines. About 400 local civilian personnel also served in the regiment. Led by Lieutenant Colonel Nouguès, the last colonel of the 5e REI, the new 5e RMP was divided into an HQ battalion and two construction battalions. It was stationed at Camp Arue in Papeete, the capital of French Polynesia.
The new regiment took over the regimental colors, history, and traditions of the disbanded 5e REI.
As an overseas unit, as was its original predecessor from the 1930s, it consisted of volunteers who rotated on a regular basis under a two-year individual stay assignment and received a far better monthly salary.
The main tasks of the 5e RMP were building and guarding a new French nuclear test site in Polynesia, as well as its support facilities and infrastructure, to replace the one operating in Algeria’s Sahara from 1960. Paris couldn’t keep the nuclear experiments center there given that Algeria had gained its independence from France.
In January 1964, the last detachment of former 5e REI legionnaires landed in Tahiti and reinforced the regiment.
In April, the 2nd Battalion moved to Hao Atoll, located about 600 miles (some 900 km) east of Tahiti, to build a forward operating base there.
The same month, the regiment was reorganized. The battalions were disbanded. Now the 5e RMP comprised seven companies: an HQ company, a heavy equipment company, two construction companies, and three logistics support companies. They remained based on Mururoa and Hao, with the HQ in Papeete.
In August 1965, military facilities were built on several atolls surrounding Mururoa. Also, construction work was carried out on the island of Mangareva.
In October, the regiment was taken over for the first time by a non-Legion commanding officer from the Engineer Corps. A Legion officer served as his deputy.
In 1966, the Pacific Testing Center (Centre d’Expérimentation du Pacifique, CEP) was finished. It launched its first nuclear test on Mururoa on July 2.
The regiment continued to carry out its missions: build and maintain military facilities, carry out construction tasks in support of the testing site, protect the testing site and the surrounding area, and help improve the local infrastructure in Polynesia.
Construction of another nuclear testing site began on Fangataufa Atoll, 23 miles (37 km) south of Moruroa. Two years later, in August 1968, the first test of a thermonuclear weapon (H-bomb) took place there.
In 1971, the regiment was assigned additional missions: maintaining and repairing military vehicles and heavy equipment for all French forces in Tahiti; providing electric power distribution for Papeete, Hao, and Mururoa; and providing potable water distribution for Hao, Mururoa, and Fangataufa.
The 5e RMP left Camp Arue in Papeete four years later, in 1975, and was fully installed on Mururoa Atoll. Only a small logistics detachment remained in the former HQ. From the same year onward, the commanding officer was replaced every year, unlike in other French regiments (including the Legion’s), in which there is an established two-year period of command.
Around 250 local civilian employees served with the regiment at the time.
In the mid-1970s, the 5e RMP comprised:
- HQ & Service Company (CCS)
- Construction Company (CT)
- Heavy Equipment Company (CE)
- Water Company (CEE, seawater desalination)
- Transportation & Repair Company (CTR)
- Logistics Support Detachment (Camp Arue, Papeete)
In 1977, the regiment carried out work on the Gambier Islands and on Hao.
The next year, on January 14, 1978, the 5e RMP legionnaires stopped a rebellion and restored order in the biggest prison of French Polynesia, Nuutania.
From 1979 to 1982, work continued on Fangataufa. In the meantime, in 1981, legionnaires had to rebuild military facilities on Mururoa, which had been damaged by a tropical cyclone, as well as the sea wall protecting the atoll. From October to May 1982, the 3rd Squadron 1er REC deployed from France to Mururoa to help with reconstruction work.
After other tropical cyclones damaged Mururoa, the decision was made to build a solid barrier around the atoll: the Pacific Wall (Mur du Pacifique). This work began in 1983.
The next year, a significant reorganization took place in the French Army. It also affected French Polynesia and the 5e RMP. Therefore, on June 30, 1984, the 5th Pacific Mixed Regiment formally ceased to exist.











5th Foreign Regiment from 1984 to 2000
On Mururoa, the 5e RMP was reorganized and redesignated on July 1, 1984. It became the 5th Foreign Regiment (5e Régiment étranger, 5e RE). The regiment was now considered a pure Foreign Legion unit. Legionnaires comprised a majority of its personnel. However, French regular engineering and logistics elements still served with the unit, as did local civilians.
The new regiment took over the tasks of its predecessor. Lieutenant Colonel Albaladejo became its first commanding officer.
Later that year, in Mururoa, the 5e RE built a solid runway that was a mile and a half long (2,400 m). Even heavier transport aircraft could land on it.
In 1986, the Pacific Wall protecting the military base on the atoll was finished. The wall was up to 7.5 feet (220 cm) high and several miles long. It was built with some 14,000 tons of reinforced concrete for 1 km (0.62 mi), fabricated by the regiment on the spot.
From 1986 to 1988, the legionnaires repaired the local infrastructure on the Marquesas, on the Wallis and Futuna Islands, and in the Cook Islands (the latter governed by New Zealand), which had suffered damage from cyclones.
In 1987, the legionnaires restored order on the Marquesas Islands. They did the same thing in Papeete the next year.
Between 1988 and 1990, the 5e RE built a runway on Hiva Oa, the second-largest island in the Marquesas.
In addition, in the 1980s, a road tracing the perimeter of Mururoa Atoll was restored and enlarged. It was almost 20 miles (30 km) long.
In early February 1990, the regiment received its new regimental colors.
Three months later, the Intervention Company – nicknamed the Caravelle (Caravel) Company – was established. An operational element of the regiment, it maintained the primary mission of guarding the airport of Mururoa. Furthermore, it was to be ready to quickly deploy anywhere in the region if needed.
In 1991, the 5e RE finished a runway on Rurutu, the northernmost island of the Austral Islands.
That same year, French nuclear tests were suspended due to geopolitical changes.
Between 1992 and 1995, the regiment carried out various reconstruction and repair tasks on the damaged islands, including Rurutu, Wallis, and Futuna. Construction work was organized on Rikitea, part of the Gambier Islands, and Nukutavake, in the Tuamotu Islands. Also, a runway was built on Takume Atoll and the island of Ahe.
In 1995, the 5e RE comprised:
- HQ & Service Company (CSBI)
- Combat & Construction Company (CCT)
- Transportation & Repair Company (CTR)
- Intervention Company (CI)
That same year, the French atomic bomb tests resumed, though not for long. The last nuclear test on Polynesia was carried out on January 27, 1996, on Fangataufa. Later that year, the United Nations adopted a multilateral treaty to ban nuclear weapons testing.
Therefore, new military facilities were constructed on Hao Atoll, where the entire 5e RE was transferred in 1997. On Mururoa, all installations that once accommodated about 3,000 people had to be dismantled and removed. The same applied to the installations on Fangataufa. The work lasted until 1998.
From July 1997, the regiment was reduced to the HQ & Service Company (CCBS) and the Construction Company (CT).
Once all the military installations on Mururoa and Fangataufa had disappeared, a platoon of legionnaires guarded each site. The platoon was replaced every two months.
During the last period of their stay in Polynesia, from 1998 to 2000, the 5e RE men built a runway on Hikueru Atoll and carried out construction work on Mangareva.
The last 5e RE legionnaires left French Polynesia in May 2000. On June 30, the 5th Foreign Regiment was officially inactivated. In September, its flag was deposited in the Legion’s Hall of Honor in Aubagne, Southern France.
It took 24 long years before a new page in the history of the old “Regiment of Tonkin” would start to be written. This time, it was on Mayotte, an island in the Indian Ocean, where the Foreign Legion Mayotte Detachment (DLEM) was transformed into a new 5th Foreign Regiment in late 2024. The legend continues…













———
5e RE’s Regimental song: Le front haut et l’âme fière
———
Main information sources:
Képi blanc magazines (1954 – 2000)
Légion étrangère magazines (1937 – 1944)
Vert et Rouge magazines (1945 – 1955)
Foreign Legion annual bulletins (1954 – 1964)
Tibor Szecsko: Légion étrangère en Indochine, 1914-1941 (Edi-Cats, 1989)
Jean-Paul Mauhualt: Le Grand 5, 1883-2000 (Editions L’Harmattan, 2006)
Pierre Dufour: Génie-Légion (Lavauzelle, 2000)
Alain Gandy: La Légion en Algérie (Presses de la Cité, 1992)
Fanion Vert et Rouge
More Majorum – German legionnaires in Indochina, 1945-56
———
———
Learn about other Foreign Legion units:
1st Foreign Parachute Regiment
2nd Foreign Cavalry Regiment
3rd Foreign Parachute Regiment
4th Foreign Infantry Regiment
6th Foreign Infantry Regiment
Foreign Regiments Joint Depot
11th Foreign Infantry Regiment
———
The page was updated on: October 5, 2024