Indian Army Act, 1911

Indian Army
Star of India Red Ensign
Active	1895–1947
Country	India
Allegiance	British Empire
Branch	Army
Size	First World War: ~1,750,000 Second World War: ~2,500,000
Headquarters	GHQ India
Equipment	Lee–Enfield
Engagements	Second Anglo-Afghan War Third Anglo-Afghan War Third Anglo-Burmese War Second Opium War Anglo-Egyptian War British Expedition to Abyssinia First Mohmand Campaign Boxer Rebellion Tirah Campaign British expedition to Tibet Mahdist War First World War Waziristan campaign (1919–1920) Waziristan campaign (1936–1939) Second World War North-West Frontier (1858–1947)
Commanders
Notable commanders	Frederick Roberts William Birdwood William Slim Claude Auchinleck Edward Quinan

First World War: ~1,750,000

The Indian Army was the principal army of India before independence from the United Kingdom in 1947. It was responsible for the defence of both British India and the princely states, which could also have their own armies. The Indian Army was an important part of the British Empire's forces, both in India and abroad, particularly during the First World War and the Second World War.

The term "Indian Army" appears to have been first used informally, as a collective description of the Presidency armies (the Bengal Army, the Madras Army and the Bombay Army) of the Presidencies of British India, particularly after the Indian Rebellion. The first army officially called the "Indian Army" was raised by the government of India in 1895, existing alongside the three long-established presidency armies. However, in 1903 the Indian Army absorbed these three armies. The Indian Army should not be confused with the "Army of India" (1903–1947) which was the Indian Army itself plus the "British Army in India" (British units sent to India).

The Indian Army has its origins in the years after the Indian Rebellion of 1857, often called the Indian Mutiny in British histories, when in 1858 the Crown took over direct rule of British India from the East India Company. Before 1858, the precursor units of the Indian Army were units controlled by the Company and were paid for by their profits. These operated alongside units of the British Army, funded by the British government in London.