The fall of Mandalay on 20th March 1945 was the culmination of an advance of 640 kilometres (400 miles) against ever increasing opposition which carried the 19th Indian Division of the British Indian Army from the banks of the Chindwin River to the walls of Fort Dufferin in Mandalay. Both the 1st and 4th Battalions of the 6th Gurkha Rifles served in the 19th Indian Division during this period. The 1st Battalion was in the 64th Indian Infantry Brigade, for the most part leading the Divisions advance and covering the north and west flanks. The 4th Battalion was in the 62nd Indian Infantry Brigade. It was this lightening advance over difficult and sometimes treacherous terrain chasing a tenacious and often fanatical enemy that was a principal factor in the defeat of the Japanese.