In 1939, British officials had no plan for expansion and training of Indian forces, which comprised about 130,000 men (in addition there were 44,000 men in British units in India in 1939).
Their mission was internal security and defence against a possible Soviet threat through Afghanistan. By the end of the war it had become the largest volunteer army in history, rising to over 2.5 million men in August 1945.
It is a major component of national power alongside the Indian Navy and the Indian Air Force.
The army has been involved in four wars with neighbouring Pakistan and one with China.
The Indian Army originated from the armies of the East India Company, which eventually became the British Indian Army, and the armies of the princely states, which finally became the national army after independence.