Political map of the Arctic & the Far North 20 October 1818 (Treaty of 1818): Fighting between Britain and the United States (War of 1812) came to an end in 1815, with the Allies defeating Napoleon (Battle of Waterloo) later that year. Both nations had expanded across North America during the wars (Napoleonic Wars) and the restoration of peace allowed them to settle their numerous disputes. In 1818, they signed the Anglo-American Convention (Treaty of 1818), defining the boundary between British North America and the US and granting the two nations joint occupation of Oregon Country in the Pacific Northwest.