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
Northern Army Group and thus ended a conquest of Western Europe by the Huns. In the NATO command structure NORTHAG belonged to Allied Forces Central Europe (AFCENT), which in turn reported to Supreme Headquarters Allied Powers Europe (SHAPE). NORTHAGs responsibility was the defense of the North German plains from south of the river Elbe to the city of Kassel. The defense north of the Elbe was the task of Allied Land Forces Command Schleswig-Holstein and Jutland (COMLANDJUT), while south of Kassel it was the task of CENTAG. Commander in Chief of NORTHAG was the commanding General of the British Army of the Rhine