In late March 1944, the Japanese launched the invasion of India from Burma. British Gen William Slim, the 14th Army commander, was poised to invade Burma but wished to kill as many Japanese as possible prior to it. The invasion of India was the perfect opportunity and Slim planned to concentrate his troops on the Imphal plain to do so. Unfortunately, the Japanese were more numerous than he thought, many of his troops were still too far from the battle, and “most distressingly”, the Japanese moved faster than Slim expected.
While Slim was sorting out the battle on the Imphal plain, Japanese Maj Gen Kotaku Sato’s 31st Division made a lightning fast forced march thru the jungle toward Kohima, the halfway point on the crucial Dimapur to Imphal supply route. (Dimapur was Slim’s railhead and main logistics area). Slim’s box tactics allowed his soldiers to be cut off temporarily, but the loss of Kohima would prevent all ground supply from reaching Imphal and there wasn’t enough air transport in Southeast Asia and India to supply his four divisions. The 31st Division’s advance was rapid, but they were opposed by a single battalion from the Assam Regiment and some Assam policemen over the last 60 miles. They heroically delayed Sato for four critical days before the Japanese could reach Kohima.
Those four days allowed Col. Hugh Richards to organize an ad hoc defense of Kohima centered on the ridge east of the road. Thousands of noncombatants were evacuated and any soldiers who knew how to handle a rifle were organized into units and dug in. Richards had only the 2500 soldiers, including 450 men of the 4th Bn of the Queen’s Own Royal West Kents, part of a heaven sent Rajput machine gun Bn, 400 men of the Shere Regt of the Royal Nepalese Army, the remains of the Assam Bn (when they arrived from delaying the Japanese) and 500 convalescents and transients from the hospital and way station in Kohima, to fight the 13,500 approaching Japanese. On 3 April 1944, the Japanese surrounded the town. The Battle for Kohima began the next day.
For the next 13 days, the besieged Allies faced suicidal but effective human wave assaults, and brutal hand to hand combat all along Kohima Ridge. Rajput machine guns and British artillery melted down because of their rapid and continuous fire in the 120 degree heat. The battle eventually focused on the Allies’ critical vulnerability: water. By 16 April, the Allies were down to one pint of water per man per day. Eventually, the thirsty remnants of Richard’s defenders were forced back into a 500m by 500m box on Garrison Hill which contained a small spring outside of the old district commissioner’s house. The only thing separating the spring from the Japanese was the commissioner’s garden and tennis court. On the night of 16/17 AprIl, the Japanese, who had suffered 8000 casualties by this point, tried one last banzai charge across the tennis court to capture the spring. The “Battle of the Tennis Court” raged all night, but by dawn it was obvious the Japanese would not succeed.
On the 19th, the Indian 161st Brigade of the British 2nd Division, attacking from Dimapur, broke through to Garrison Hill. The next day, the Japanese dug in and prepared for the inevitable Allied counterattack.