India Command

Following the Kitchener Reforms of 1903 during the British Raj, the Commander-in-Chief, India enjoyed control of the Army of India and answering to the civilian Viceroy of India. The Commander-in-Chief's staff was overseen by the Chief of the General Staff. GHQ India was based in Calcutta and Simla (the winter capital of the Raj) until the seat of power moved to New Delhi in 1911.

In addition to India it was responsible for varying periods parts of the Middle East (Aden in particular, as well as Iraq and Persia). For significant periods before the creation of South East Asia Command (SEAC) in 1943 the C-in-C India was also responsible for Ceylon and Burma.

The Commander-in-Chief, India had some 2,000 officers and 2.5 million troops under his command in 1945. GHQ India was redesignated Army HQ in 1947 when India was partitioned.

Following a review by the British Chiefs of Staff in late 1939, operational control of troops in Iraq passed in early 1940 to Middle East Command although the provision of troops and their maintenance remained for the most part GHQ India's responsibility. In March 1941, in the period before the Anglo-Iraqi War, the C-in-C Middle East General Archibald Wavell, who was preoccupied with existing problems in his theatre, gained approval for Iraq to come under India's operational control again but once hostilities commenced in May Wavell was obliged by London reluctantly to reassume responsibility. In June 1941, after cessation of hostilities, control reverted once more to GHQ India. India finally relinquished responsibility for Persia and Iraq in August 1942 when a separate Persia and Iraq Command was created.

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Wikipedia