The Convention of 1818 arose out of ongoing tensions between the United States and Great Britain regarding territorial claims in North America after the War of 1812. Before this agreement, the boundary between the U.S. and British North America was largely undefined, leading to conflicts over land ownership and governance. The delegates agreed to create a definitive border that would run primarily along the 49th parallel, extending from the Lake of the Woods in the east to the Rocky Mountains in the west. This effectively settled the southern limit of British North America, now Canada, and simplified governance of the regions involved.

Notably, the agreement allowed for the joint occupation of the Oregon Territory, further solidifying diplomatic relations and ensuring a peaceful coexistence in an area rich with resources and potential for development. With the United States steadily expanding westward, recognizing a stable boundary was essential for both nations in avoiding conflicts that could arise out of territorial disputes. Moreover, it reflected the growing importance of diplomacy over military engagement in resolving international disputes.

The signing took place at a time when both countries were recovering from the War of 1812, leading to a desire for cooperation instead of conflict. The Convention was signed by U.S. Secretary of State John Quincy Adams and British Foreign Secretary Lord Castlereagh. This landmark agreement laid the groundwork for future negotiations, contributing to a long-term peaceful coexistence between the United States and Canada, which would eventually lead to further border adjustments and a deeper relationship between the two countries.