Supreme Headquarters Allied Powers Europe Supreme Headquarters Allied Powers Europe Supreme Headquarters Allied Powers Europe (SHAPE) is the headquarters of the North Atlantic Treaty Organization's Allied Command Operations (ACO). SHAPE is located at Casteau, north of the Belgian city of Mons. The commander of ACO and SHAPE is Supreme Allied Commander Europe (SACEUR), a U.S. four-star general officer or flag officer who also serves as Commander, U.S. European Command. Since 1967 it has been located at Casteau, north of the Belgian city of Mons, but it had previously been located, from 1953, at Rocquencourt, next to Versailles, France. From 1951 to 2003, SHAPE was the
Western Union (alliance) 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, while the physical headquarters in Fontainebleau were transformed into NATO's Headquarters, Allied Forces