The Battle of Imphal involved the Japanese and INA units attacking Manipur from three broad directions in March 1944: the 15th Division from the north/north-east; Yamamoto Force of the 33rd Division from the southeast; and the rest of 33rd Division from the south/south-west. The British had always planned to withdraw their two forward Divisions deployed along and beyond the India-Burma border – the 20th Indian Division at Tamu and the Kabaw Valley and the 17th Indian Division at Tiddim – to the edges of the Imphal Valley at the first sign of a Japanese attack. The idea was to fight the latter in conditions favourable to the British.
Despite some scares, this was ultimately achieved as the Japanese were forced to fight at the end of a long and precarious supply line extending all the way back from Manipur over the mountains to the Chindwin River in Burma. Confronted with mounting logistical difficulties, the onset of the monsoon, and a better trained and supported – medically and from the air – opponent, the Japanese attack failed and its forces, together with INA units, were forced to return to Burma by July 1944.
In his memoir Defeat into Victory, General William J. Slim (later Field Marshal Viscount), commander of the British 14th Army and the one who led it to victory in the Burma Campaign, describes the fighting in Manipur as follows: ‘Like unevenly spaced spokes of a wheel, six routes converged on to the Imphal plain to meet at the hub, Imphal itself:
(i) From the north, the broad Kohima road
(ii) Also from the north, the footpath down the Iril River Valley
(iii) From the north-east, the Ukhrul road
(iv) From the south-east, the tarmac Tamu-Palel road
(v) From the south, the rugged Tiddim highway
(vi) From the west, the Silchar-Bishenpur track
It was by these that the Japanese strove to break into the plain. The fighting all round its circumference was continuous, fierce, and often confused as each side manoeuvred to outwit and kill. There was always a Japanese thrust somewhere that had to be met and destroyed. Yet the fighting did follow a pattern. The main encounters were on or near the spokes of the wheel, because it was only along these that guns, tanks and vehicles could move’.