Cover photo: General Frank Merrill, commander of the famed “Merrill’s Marauders,” with two Japanese-American soldiers in northern Burma (May 1, 1944).

With the Japanese dominance in Burma during World War II, the British retreated to India, cutting off the “Burma Road,” a narrow supply route barely keeping China in the war. The steep mountains and dense jungle in the northern part of the country made it an extremely challenging environment for conventional warfare. The recommendation of a long range penetration special operations jungle warfare unit of USArmy was necessary.

In October 1943, a secret Ranger unit was established in Bombay, India, the 5307th Composite Unit (Provisional), which soon earned the nickname “Merrill’s Marauders” from their leader, Brigadier General Frank Merrill. The Caribbean Defense Command provided 960 officers and men trained in jungle warfare, 970 officers and men trained in jungle warfare came from the army’s ground forces (based in the Continental United States), and another 674 veterans came from the South Pacific Command (veterans of the Guadalcanal and Solomon Islands campaigns).

In February 1944, 2,750 “Raiders” divided into 3 Battalions arrived in Burma and embarked on a 5-month epic march behind Japanese lines. The unit’s transport company, equipped with mules, played a significant role. The mules were used to carry radios, ammunition, and heavier support weapons, including M1A1 2.36-inch bazookas and 60mm M2 mortars.

Weight was crucial for the Marauders, and the need for a compact, lightweight field ration was essential. The 4,000-calorie-a-day jungle ration had been discontinued for cost reasons in 1943, and based on the advice of Army supply officers in Washington, General Stilwell and his G-4 staff provided the daily issue of the 2,830-calorie K-ration (one K-ration = three meals) of the U.S. Army, which they believed would be sufficient. Additionally, a little-known secret to the Marauders’ success was the presence of fourteen Japanese-American Military Intelligence Service translators assigned to the unit, including the distinguished Roy Matsumoto.

Using their agility and surprise, the Marauders continuously harassed the enemy’s supply and communication lines, neutralized patrols, and carried out attacks behind Japanese lines: in one instance, they cut off the Japanese rear guard at Maingkwan. Near Walawbum, the 3rd Battalion surprised the Japanese, killing approximately 400–500 enemy soldiers.

At Nhpum Ga, the Marauders neutralized 400 Japanese soldiers while suffering 57 dead in battle, 302 wounded, and 379 more incapacitated due to illness and exhaustion. Of the unit’s remaining 200 mules, 75 were killed by artillery and mortar fire. A simultaneous outbreak of dysentery (after connecting with allied Chinese forces) further reduced their effective strength. Although the Marauders had previously avoided losses from this deadly disease (partly by using halazone tablets and strict hygiene procedures), their camp with Chinese infantry, who used rivers as latrines, caused significant damage (the Chinese troops, who always boiled their drinking water, were not seriously affected).

On May 17, 1944, after an exhausting 100-kilometer march over the 2,000-meter-high Kumon Mountains (using mules to transport supplies), about 1,300 remaining Marauders, along with elements of the 42nd and 150th Chinese Infantry Regiments, attacked the unsuspecting Japanese at Myitkyina airfield. Despite the initial successful surprise, the forces were insufficient to capture the city itself, and the first Chinese attacks were repelled with heavy losses. The Marauders had to continue fighting at the height of the monsoon season, further worsening their situation. It was also revealed that the area around Myitkyina had a high frequency of scrub typhus, from which some Marauders suffered after sleeping in infected areas.

Terribly strained by bloody dysentery and fevers, with their only rest and sleep space in the mud, the Marauders attacked and defended in a series of hard-fought infantry battles with the Japanese forces. After reinforcement by an airborne division of the Chinese army, the city finally fell to the Allies on August 3, 1944. The Japanese commander escaped with about 600 of his men. 187 Japanese soldiers were captured, and the rest, about 3,800 men, were killed.

In their final mission, the “Raiders” suffered 272 dead, 955 wounded, and 980 sick from the dozens of tropical diseases.¹ Merrill himself refused evacuation after a heart attack but finally did so when malaria set in. Some men later died from cerebral malaria, amoebic dysentery, and/or typhus. A tragic irony was that the Raiders evacuated from the front lines received jungle hammocks with protective mosquito netting and rain covers to sleep in, equipment that could have prevented various diseases and losses if provided earlier in the campaign. Only 200 Raiders remained active at the end of the campaign.

In over five months, the Marauders had traveled 1,300 km through some of the world’s most demanding jungle terrain, fought in five major battles (Walawbum, Shaduzup, Inkangahtawng, Nhpum Ga, and Myitkyina), and engaged in another 32 minor skirmishes. Fighting Japanese soldiers, hunger, fevers, and diseases, they had traversed more jungle terrain than any other American army formation during World War II.

Sources:

H. Nelson, “Merrill’s Marauders (February-May 1944)”, publ. Center of Military History of USArmy, Washington, 1990.

European Center of Military History, 5307 (P)(C) (Merril’s Marauders) GALAHAD – Burma – April-May 1944

Allied Armies in Burma Battle Japanese on Wide Front etc. (1944), publ. National Archives and Records Administration, 1944.

Allies win Myitkyina airstrip (1944), publ. National Archives and Records Administration, 1944.

Youtube/ PublicResourceOrg/Merrill’s Marauders

1. Official figures of The Adjutant General’s battle casualty roster report 424 casualties during the march and battles (of which 123 were Killed in action and 8 missing) and 1.970 disease casualties for a total of 2.394 casualties from February to June, 1944 ↩︎