Y Force

Y Force was the South East Asia Command designation given to Chinese National Revolutionary Army forces that re-entered Burma from Yunnan in 1944 as one of the Allies fighting in Burma Campaign of World War II. It consisted of 175,000 troops divided into 15 divisions.

When the Japanese invaded Burma (in the first half of 1942), the Chinese Expeditionary Force in Burma, along with the other Allies forces, were forced to retreat back along their lines of communications. Most of the Chinese retreated into China but two divisions (38th and 22nd, plus fragments of three others) retreated into India where they were placed under the command of the American General Joseph Stilwell.

After being re-equipped and retrained the Chinese divisions designated X Force formed the majority of front line forces available to Stilwell when he advanced into Northern Burma in October 1943. His intention was to capture Northern Burma and reopen land communications with China via a new spur to the Burma Road called the Ledo Road.

In support of Stilwell's offensive, in the second half of April 1944, Y Force mounted an attack on the Yunnan front. Nearly 75,000 troops crossed the Salween river on a 300 kilometres (190 mi) front. Soon some fifteen Chinese divisions of 175,000 men, under General Wei Lihuang, were attacking the Japanese 56th Division. The Japanese forces in the North were now then fighting on two fronts in northern Burma.

By the end of May the Yunnan offensive, though hampered by the monsoon rains and lack of air support, succeeded in annihilating the garrison of Tengchung and eventually reached as far as Lungling. Strong Japanese reinforcements then counter-attacked and halted the Chinese advance.

During the monsoon season there was a pause in major offensive actions and the fighting did not resume in earnest until later in 1944.

The Japanese Thirty-third Army, led by Lieutenant General Masaki Honda, defended Northern Burma against attacks from both Northern India and the Chinese province of Yunnan. The Japanese 18th Division faced the American and Chinese forces advancing south from Myitkyina and Mogaung which the Allies had secured in 1944, and the Japanese 56th Division faced the large Chinese Yunnan armies led by Wei Lihuang.

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