Involved in the Battle of Imphal were more than 120,000 men of the British 14th Army, including a mix of Gurkhas, Indians and the British. They made up the Imphal-based 4th Corps of the British 14th Army, which initially consisted of three infantry Divisions – the 17th, 20th and 23rd Indian Divisions – as well as the 50th Indian Parachute Brigade and the 254th Indian Tank Brigade. The commander of the 4th Corps was Lieutenant General Geoffrey Scoones.
Later, two Brigades from the 5th Indian Division and one from the 7th Indian Division were flown to the Imphal front from the Arakan in Burma (present-day Rakhine State in Myanmar) in March and May 1944 respectively.
Besides regular forces in Manipur, the British had in place ‘V’ Force in the mountains to the east/north-east and west/south-west of Imphal. It was tasked with gathering information on Japanese movements along, and near, the India-Burma border.
On the Japanese side in Manipur were around 70,000 men, including two Divisions – the 15th and the 33rd – of its 15th Army. A third Division – the 31st – of some 20,000 men headed towards Kohima, some of whom went via Ukhrul. The commander of the Japanese 15th Army was Lieutenant General Renya Mutaguchi.
Over 7,000 men from the INA’s 1st Division also participated in the Battle of Imphal. This included the Gandhi and Azad Brigades, part of the Subhash Brigade, as well as INA Special Groups attached to the Japanese Divisions.