In the mid-1840s, the tidal wave of American immigration, as well as an American political movement to claim the entire territory, led to a renegotiation of the agreement. The Oregon Treaty of 1846 established the 49th parallel as a long-term border between the United States and British North America and the Pacific Ocean. [Citation required] Several other separate committees identified other sections of the border that negotiators had drawn using erroneous maps during the Treaty of Paris of 1783. The commissions shared the St. Lawrence and other rivers that connect the Great Lakes to allow the two countries to navigate canals, and handed Wolfe Island to Kingston, Ontario, to the British and to the Greater Island near Detroit in the United States. British and American negotiators also agreed to make the present Angle Inlet, Minnesota the final point of the 1783 border, and to allow the 1818 convention concluded by Rush and Albert Gallatin to determine the border west of that point. The treaty was negotiated for the United States by Albert Gallatin, Ambassador to France, and Richard Rush, Minister to the United Kingdom; and for the United Kingdom, by Frederick John Robinson, treasurer of the Royal Navy and a member of the Council of Privileges, and for Henry Goulburn, a secretary of state.  The treaty was signed on 20 January 1819 The ratifications were exchanged.  The 1818 Convention, with the Rush Bagot Treaty of 1817, marked the beginning of improved relations between the British Empire and its former colonies, paving the way for more positive relations between the United States and Canada, despite the fact that the defence of the American invasion was a defence priority in Canada until 1928.  Although the agreements on border disputes and trade agreements have not fully resolved, the Rush Bagot Agreement and the 1818 Agreement marked a significant turning point in Anglo-American and U.S.-Canadian relations. American political leaders had long expressed an interest in disarming the Great Lakes and had proposed such a measure in the negotiations that led to the Treaty of Jay of 1794, but British officials had rejected this proposal.
During the War of 1812, Britain and the United States had built fleets of ships on the lakes of Erie and Ontario and had fought many battles in the region. By the end of the war, American forces had acquired supremacy over the lakes. After the war, the two powers were cautious with the military force of the other, followed by a race to shipbuilding after the war. But both countries also wanted to reduce their military spending. Unfortunately, the Treaty of Gant, which ended the war, contained no disarmament provisions. However, it has set up commissions to eliminate disputed areas along the border (as stipulated in the Paris Treaty of 1783) between the United States and British North America. While these commissions were debating border issues, Rush and Gallatin concluded the Anglo-American Convention of 1818, which notably confirmed the permanent rights of the United States to fish off Newfoundland and Labrador. The convention also provided for Russian mediation on the issue of runaway slaves at the hands of the United Kingdom (American slave owners eventually obtained financial compensation) and also found that the border ran from angle Inlet in the south to the 49th parallel, and then west with the Rockies. Oregon Country would remain open for both countries for ten years. The rush bagot pact was an agreement between the United States and Great Britain to eliminate their fleets from the Great Lakes, with the exception of small patrol vessels. The 1818 convention established the border between the territory of Missouri in the United States and British North America (later Canada) at the forty-ninth parallel.