Ogdensburg Agreement

The Ogdensburg Agreement is an agreement signed on August 17, 1940, between Prime Minister Mackenzie King of Canada and United States President Franklin Roosevelt in Heuvelton near Ogdensburg, New York. It outlined a permanent plan for mutual defense overseas between the United States and Canada.

Although Canada and the United States had long been economic partners, Canada had always considered Great Britain as its primary military partner. While Canada had been granted independence in its foreign policy from Britain in 1931, Canada's membership in the Commonwealth of Nations, the strength of the British Empire, and the historic and cultural ties between them made a military alliance with the United States seem unnecessary. Most Canadians believed that Britain could provide for all of Canada's defense needs.

Canada had declared war on Nazi Germany shortly after the Second World War began in early September 1939 but the United States remained neutral. By mid-1940, the situation in Europe had grown dire; Germany's military successes had led to the occupation of most of Europe, and most importantly, France, which surrendered in June 1940. With Germany in control or allied with nearly all of continental Europe, it began to develop plans for an invasion of the British Isles. Germany's seemingly unstoppable military, its submarine campaign against British merchant shipping, and its neutrality pact with the Soviet Union, convinced many, including American President Franklin Roosevelt, that Britain itself would soon be invaded or forced to surrender.

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