Relations between the Soviet Union and the Western powers steadily deteriorated after 1945. In August 1947, Escott Reid, a senior official in Canada's Department of External Affairs, proposed the formation of a collective security organization for western Europe. The purpose of this organization would be to counter the strong Soviet military presence in eastern Europe. Louis St. Laurent, Minister for External Affairs, and his deputy minister, Lester B. Pearson, supported the idea. The following year, several negotiations took place between officials from Canada, the United States, Britain, and other western European nations.
As a result, the North Atlantic Treaty Organization was formed on 4 April 1949. Its members included Canada, the United States, Great Britain, Iceland, Norway, Denmark, Belgium, Holland, Luxembourg, France, Italy, and Portugal. During the same year, Canada tentatively agreed to commit an army brigade group and nine squadrons of fighter aircraft as part of the NATO forces being stationed in Europe. In large part because of Canada's commitment of troops to the Korean conflict, a firm decision to dispatch 27th Canadian Infantry Brigade to Germany was not announced until 4 May 1951. By December, the brigade was housed in temporary barracks in Hanover, but, in late 1953, it moved into a string of garrisons in an area east of Dortmund between Soest and Iserlohn.