Commander-in-Chief is the commander of all the military forces within a particular region or of all the military forces of a state.
In the British Army, the office of General in ChiefCommand, later renamed Commander-in-Chief of the Forces, was instituted after the Restoration in 1660.
The Constitution of the Commonwealth of Australia provides that: "The command in chief of the naval and military forces of the Commonwealth is vested in the Governor-General as the Queen's representative".
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 1672 until 1904, when the office was replaced by the Chief of the General Staff, soon to become Chief of the Imperial General Staff.
The relationship between the Commander in Chief and another office, the Captain-General, was never clear.
Instead, the British Army was represented variously in government by the Paymaster of the Forces (Paymaster-General), Master-General of the Ordnance, Secretary at War, Secretary of State for War and the Colonies, Secretary of State for War or Secretary of State for Defence.