The War Office was a department of the British Government responsible for the administration of the British Army between the 17th century and 1964, when its functions were transferred to the Ministry of Defence.The name "War Office" is also given to the former home of the department, the War Office building located at the junction of Horse Guards Avenue and Whitehall in central London. In August 2013 it was announced that the War Office building would be sold on the open market.