Early in 1944 the Japanese 15th Army commanded by Lieutenant General Renya Mutaguchi launched a pre-emptive strike across the Chindwin River. Its primary aim and purpose was to encircle and destroy the Indian IV Corps at Imphal to prevent the launch of a British & Indian attack across the border to retake Burma.
To achieve this Mutaguchi ordered 2 of his divisions, the 15th & 33rd to encircle and destroy the British and Indian forces on the Imphal Plain. His 3rd Division, the 31st, commanded by Lieutenant General Kotoku Sato was to strike west to cut the road between the great supply depot and railhead at Dimapur thus preventing reinforcements from going to the aid of IV Corps. The road was to be cut at the small hill station of Kohima which sat at the pass through the hills. Once this was achieved, Mutaguchi further planned to advance into India proper. He was convinced that the Indians would then rise up in support against the British. This, the Japanese claimed, was the start of their ‘March on Delhi’.
The British of course knew that the Japanese were heading towards Kohima but they didn’t fully appreciate the numbers and the speed of approach. The Japanese 31st Division comprised about 15,500 men!!
Kohima was almost like a transit camp, with soldiers coming and going all of the time as the build up in Imphal progressed. There was a field bakery, a hospital, vehicle repairs, a leave camp and a battle casualty replacement camp. With the constant movement of men, the best estimate is that the Garrison, commanded by Colonel H.U.W. Richards, consisted of about 1,500 combatant troops. These were mainly 420 officers & men from the 4th battalion of the Queens Own Royal West Kent (4 RWK) regiment who together with the remainder of their brigade, the 161st from 5th Indian Infantry Division had been airlifted out from the Arakan to meet the threat.
Elements of the Assam Rifles and Assam Regiment together with the soldiers from the leave & casualty replacement camp formed the remainder. The Japanese arrived in the Kohima area on the 4th April and by the 5th they were fully engaged with the garrison. Slowly, day by day, the defenders were inexorably driven in on their final defensive position – the Deputy Commissioner’s tennis court and bungalow.
In the meantime, the British 2nd Division was some 2000 miles away in the south west of India centred on Belgaum. To meet the emergency, the Division was rushed across India by road, rail and air. Speed was of the essence because the Japanese had also cut the Dimapur / Kohima road and the small Garrison was completely surrounded. In Kohima itself, the Garrison was holding on, but was very nearly at the limit of its endurance. There was no time to form a proper divisional concentration at Dimapur and, as units of the 2nd Division arrived, they went straight into action, piecemeal.
On 12th Apr 44, 1st battalion Queen’s Own Cameron Highlanders, with artillery and tank support, attacked and destroyed the Japanese position at Zubza, near the thirty-seventh milestone. 2nd Division’s operations to relieve 161st Brigade and the Kohima Garrison went on rapidly and on Tuesday 18th April 1944, the small garrison was relieved and the siege lifted. The Japanese advance had been checked. The invasion of India had been halted. From the time orders were received at Belgaum more than 2,000 miles away, the British 2nd Division had taken only thirty one days to collect, organize and transport itself to engage with the enemy and to begin to push it back.
The immediate future, however, was forbidding. The Japanese still held most of the Kohima Ridge. Their positions, dug deep into commanding hillsides with interlocking, mutual fire support, were very strong. The fighting went on for a further 7 weeks before the Japanese were finally forced to withdraw from the field. The leading elements of the relieving column from the British and Indian army heading towards Imphal met the advance column of IV Corps at milestone 109 on the 22nd June. The Battle for Kohima was over!
The Japanese left behind around 7,000 dead and the British & Indian Army had around 4,000 casualties.
In the aftermath of the battle it has been said that there had been longer sieges but there had been few bloodier.
This was a battle in which everyone took part. There were no onlookers. The fighting was hand to hand for the most part. No-one was spared. Two Brigadiers were wounded and two more Brigadiers were killed as were five Commanding Officers as testimony to the ferocity of the fighting.
The Battle of Kohima, in the opinion of many, was the decisive period of the Burma campaign. Had Kohima fallen it is difficult to see how Imphal could have been relieved in time.
More detailed works exist which go into greater detail about the Battle and associated actions.
Memories of a Forgotten War: The First Look by Utpal Borpujari
Japan’s Last Bid for Victory: The Invasion of India, 1944 by Robert Lyman
Kohima 1944 (Campaign) by Robert Lyman and Peter Dennis