The Commander-in-Chief of the Forces, or just the Commander-in-Chief (C-in-C), was the professional head of the British Army from 1660 until 1904, when the office was replaced by the Chief of the General Staff, soon to become Chief of the Imperial General Staff (from 1909). From the passing of the War Office Act 1870, as part of the Cardwell reforms, the C-in-C was made subordinate to the Secretary of State for War.