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In 1818, at the initiative of the U.S. Secretary of State John Quincy Adams, negotiations on the U.S.-Canadian border and Oregon membership began in London. U.S. commissioners Albert Gallatin and Richard Rush proposed that the 49th parallel be considered the border between Canada and the United States along its entire length from ocean to ocean.

Explanation:

British representatives Henry Goulburn and Frederick John Robinson agreed to recognize the demarcation of this parallel only from Lake Woodland to the Rocky Mountains. Oregon was thus officially declared disputed, and the Rocky Mountains became its eastern border Negotiations resulted in a convention on the joint Anglo-American occupation of the Colombian Basin. The region retained freedom of navigation, trade and settlement for representatives of any country.

The second Anglo-American negotiations were held in London in the winter of 1823-1824. There, the Americans, represented by Richard Rush, offered the British as the 51st parallel to Oregon. The English position, presented by Henry Goulburn, consisted in division of the disputable territory on the riverbed of the Columbia. Negotiations reached an impasse, and after the proclamation of the famous “Monroe Doctrine” by the United States, negotiations were interrupted altogether.

In 1826, the commissioners of both countries met again in London. Instructions to the American representative Albert Gallatin was signed personally by President Adams, and Britain was represented by the Minister for Foreign Affairs, Sir George Canning.

The Americans again insisted on 49 parallels, but were ready to recognize the right of England to freely navigate the southern tributaries of Colombia. This “commitment” of the Americans to the 49th parallel can be explained by their hatred for the British, and their desire to reduce their presence on the continent (the 49th parallel divided the disputed territory so that there was more territory south of it than north).

After a pause in negotiations with the British, the United States documented the borders of the disputed territory. For this purpose, they negotiated with Spain and Russia, which had their interests in Oregon.