Supreme Headquarters Allied Powers Europe of "Général d'Armée" Alphonse Juin, French Army. "Holdfast" was a major allied air-ground exercise involving 150,000 British Army of the Rhine, Dutch, Belgian and Canadian troops of NATO's Northern Army Group in coordination with the Allied Air Forces Central Europe. They maneuvered east of the Rhine River in the British Zone under the overall command of Lt. General Sir Richard Nelson Gale, British Army. Finally, "Rosebud" involved ground maneuvers by the U.S. Seventh Army in the American Zone of Occupation of Allied-occupied Germany. The initial plans saw the defence of Western Europe from a Soviet invasion resting heavily on nuclear
History of the Common Security and Defence Policy while the physical headquarters in Fontainebleau were transformed into NATO's Headquarters, Allied Forces Central Europe (AFCENT). As WUDO's capacities were transferred to NATO's SHAPE, Field Marshal Bernard Montgomery resigned as Commanders-in-Chief Committee Chairman on 31 March 1951 and took the position of deputy Supreme Allied Commander Europe (SACEUR) on 1 April 1951. The establishment of NATO, along with the signing of a succession of treaties establishing the Organisation for European Economic Cooperation (April 1948), the North Atlantic Treaty Organisation (April 1949), the Council of Europe (May 1949) and the European Coal and Steel Community (April 1951), left the Western Union