The war cabinet and service ministers were usually joined by the CoS who were Admiral Sir Dudley Pound, the First Sea Lord; Air Marshal Sir Cyril Newall, the Chief of the Air Staff; and the Chief of the Imperial General Staff (CIGS). The office of CIGS changed hands on 27 May when, as desired by Churchill, Field Marshal Sir Edmund Ironside was replaced by his deputy Field Marshal Sir John Dill. Ironside became Commander-in-Chief, Home Forces. Others who often took part included the Home Secretary, Sir John Anderson; the Permanent Under-Secretary of State for Foreign Affairs, Sir Alexander Cadogan; the Secretary of State for Dominion Affairs, Viscount Caldecote; and the Minister of Information, Duff Cooper.