Although tensions between Great Britain and the United States remained high along the Great Lakes, overall relations improved. Postwar trade rebounded, and British political leaders increasingly viewed the United States as a valuable trading partner, while also realizing that British North America would be expensive and difficult to defend should another war break out. When U.S. Minister to Great Britain, John Quincy Adams, proposed disarmament on January 25, 1816, British Foreign Secretary Viscount Castlereagh responded favorably. The British Government had already dispatched Charles Bagot as Minister to the United States with the intention of improving relations between the two countries.
Bagot met with Secretary of State James Monroe informally, and finally reached an agreement with his successor, Acting Secretary Richard Rush. The agreement limited military navigation on the Great Lakes to one to two vessels per country on each lake. The U.S. Senate ratified the agreement on April 28, 1818. The British Government considered a diplomatic exchange of letters between Rush and Bagot sufficient to make the agreement effective.
Several other separate committees determined other stretches of border that negotiators at the 1783 Treaty of Paris had drawn with faulty maps. The commissions divided the St. Lawrence and other rivers connecting the Great Lakes to allow both countries navigable channels, and handed Wolfe Island near Kingston, Ontario to the British and Grosse ÃŽle near Detroit to the United States. British and U.S. negotiators also agreed to make present-day Angle Inlet, Minnesota the end point of the 1783 border and to allow the Convention of 1818, concluded by Rush and Albert Gallatin, to determine the border to the west of that point.
While these commissions debated border issues, Rush and Gallatin concluded the Anglo-American Convention of 1818 that, among other things, confirmed permanent U.S. rights to fish off Newfoundland and Labrador. The Convention also made provisions for Russian mediation over the issue of escaped slaves in British hands (U.S. slaveowners were eventually provided monetary compensation) and also determined that the border from Angle Inlet would run south to the forty-ninth parallel, and then due west to the Rocky Mountains. The Oregon Country would remain open to both countries for ten years.
Although the agreements did not completely settle border disputes and trade arrangements, the Rush-Bagot agreement and the Convention of 1818 marked an important turning point in Anglo-American and American-Canadian relations.