Battle of Kohima - Prelude

Prelude

Starting on 15 March 1944, the Japanese 31st Division crossed the Chindwin River near Homalin and moved northwest along jungle trails on a front almost 60 miles (97 km) wide. Although the march was arduous, good progress was made. The left wing of the division, 58 Regiment, commanded by the division's Infantry Group commander, Major General Shigesaburo Miyazaki, was ahead of the neighbouring formation (Japanese 15th Infantry Division) when they clashed with Indian troops covering the northern approaches to Imphal on 20 March.

The Indian troops were the 50th Indian Parachute Brigade under Brigadier Maxwell Hope-Thompson, at Sangshak. Although they were not Miyazaki's objective, he decided to clear them from his line of advance. The Battle of Sangshak continued for six days. The parachute brigade's troops were desperately short of drinking water, but Miyazaki was handicapped by lack of artillery until near the end of the battle. Eventually, as some of the Japanese 15th Division's troops joined the battle, Hope-Thompson withdrew. The 50th Parachute Brigade lost 600 men, while the Japanese had suffered over 400 casualties. Miyazaki had also captured some of the food and munitions that had been dropped by the Royal Air Force (RAF) to the defenders of Sangshak. However, his troops, who had the shortest and easiest route to Kohima, were delayed by a week.

Meanwhile, the commander of the British Fourteenth Army, Lieutenant General William Slim, belatedly realised (partly from Japanese documents that had been captured at Sangshak) that a whole Japanese division was moving towards Kohima. He and his staff had originally believed that, because of the forbidding terrain in the area, the Japanese would only be able to send a regiment to take Kohima.

The Allies were already hastily reinforcing the Imphal Front. As part of this move, the infantry and artillery of 5th Indian Infantry Division were flown from the Arakan, where they had just participated in the defeat of a subsidiary Japanese offensive at the Battle of the Admin Box. While the main body of the division went to Imphal (where some units had been isolated and almost all of IV Corps' reserves had already been committed), the 161st Indian Infantry Brigade, with 24th Mountain Artillery Regiment Indian Artillery attached, were flown to Dimapur.

Slim knew that there were few fighting troops, as opposed to soldiers in line-of-communication units and supporting services, in Kohima and none at all at the vital base of Dimapur 30 miles (48 km) to the north, until 161st Brigade arrived. Dimapur contained an area of supply dumps 11 miles (18 km) miles long and 1 mile (1.6 km) wide. As the fall of Dimapur would have been disastrous for the Allies, Slim asked his superior, General George Giffard (commanding Eleventh Army Group), for more troops to protect Dimapur and to prepare to relieve Imphal.

Early in March, the 23rd Long Range Penetration Brigade was removed from Major General Orde Wingate's Chindit force, and was dispatched by rail from around Lalaghat to Jorhat, 50 miles (80 km) north of Dimapur, where they could threaten the flank of any Japanese attack on the base. Giffard and General Claude Auchinleck, the Commander-in-Chief of the British Indian Army, also prepared to send the British 2nd Division and Indian XXXIII Corps HQ under Lieutenant General Montagu Stopford from reserve in southern and central India to Dimapur, by road and rail. The 7th Indian Infantry Division was also moved by road and rail from the Arakan to Dimapur.

Until XXXIII Corps headquarters could arrive at Dimapur, the HQ of 202 Line of Communication Area under Major General R.P.L. Ranking took command of the area.