Supreme Headquarters Allied Powers Europe government offered Camp Casteau, a 2 km² Belgian Army summer training camp near Mons, which was an area in serious need of additional economic investment. In September 1966, NATO agreed that Belgium should host SHAPE at Casteau. SHAPE closed its facility at Rocquencourt near Paris on 30 March 1967, and the next day held a ceremony to mark the opening of the new headquarters at Casteau. The drawdown of the British Mediterranean Fleet, the military difficulties of the politically decided command structure, and the withdrawal of the French from the military command structure forced a rearrangement of the command arrangements
History of the Common Security and Defence Policy the signing of the North Atlantic Treaty on 4 April 1949 in Washington, DC. The need to back up the commitments of the North Atlantic Treaty with appropriate political and military structures led to the creation of the North Atlantic Treaty Organisation (NATO). In December 1950, with the appointment of General Eisenhower as the first Supreme Allied Commander Europe (SACEUR), the members of the Treaty of Brussels decided to transfer the headquarters, personnel, and plans of the Western Union Military Organisation (WUDO) to NATO. NATO's Supreme Headquarters Allied Powers Europe (SHAPE) took over responsibility for the defence of Western Europe,