Ogdensburg Declaration

United States-Canadian history

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July 1, 2026

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The Ogdensburg Declaration was a significant agreement made between U.S. President Franklin D. Roosevelt and Canadian Prime Minister W.L. Mackenzie King in Ogdensburg, New York, on August 17-18, 1940. This declaration established the Permanent Joint Board on Defense—United States and Canada, marking a commitment to cooperate on continental defense during World War II. This was a crucial step in solidifying the relationship between the two North American nations in the face of global conflict.12

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Canada
World War II
…immediately concluded an agreement at Ogdensburg, New York, with the United States for the defense of North America. Moreover, Canada now stood in the forefront of the war. After Britain, it was (prior to the U.S. entry into the war in December 1941) the second most powerful of Germany’s adversaries.…
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…immediately concluded an agreement at Ogdensburg, New York, with the United States for the defense of North America. Moreover, Canada now stood in the forefront of the war. After Britain, it was (prior to the U.S. entry into the war in December 1941) the second most powerful of Germany’s adversaries.…
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Ogdensburg
…King, from which issued the Ogdensburg Declaration, in which the two countries agreed to cooperate in the defense of the North American continent through the creation of a Permanent Joint Board on Defense–United States and Canada.
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…King, from which issued the Ogdensburg Declaration, in which the two countries agreed to cooperate in the defense of the North American continent through the creation of a Permanent Joint Board on Defense–United States and Canada.
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