Bagot met informally with Secretary of State James Monroe and eventually reached an agreement with his successor, Acting Minister Richard Rush. The agreement limited military navigation on the Great Lakes to one to two ships per country on each sea. The U.S. Senate ratified the agreement on April 28, 1818. The British government felt that a diplomatic exchange of letters between Rush and Bagot was sufficient to make the agreement effective. The Rush Bagot Pact was an agreement between the United States and Britain to eliminate their fleets from the Great Lakes, with the exception of small patrol ships. The 1818 Convention established the boundary between the Territory of Missouri in the United States and British North America (later Canada) at forty-ninth latitude. These two agreements reflected the easing of diplomatic tensions that had led to the War of 1812 and marked the beginning of Anglo-American cooperation. Although the agreements did not fully take into account border disputes and trade agreements, the Rush Bagot Agreement and the 1818 Convention marked an important turning point in Anglo-American and American-Canadian relations.
Although the treaty caused difficulties during the First World War, its terms were not changed. Similar problems arose before the Second World War, but Foreign Minister Cordell Hull wanted to preserve the agreement because of its historical importance. In 1939 and 1940, Canada and the United States agreed to interpret the treaty so that weapons would be installed in the Great Lakes, but would no longer be operational until ships left the lakes. In 1942, the United States, now at war and allied with Canada, successfully proposed that weapons be fully installed and tested in the lakes by the end of the war. Following discussions in the Permanent Joint Board on Defense in 1946, Canada similarly proposed to interpret the agreement to allow the use of ships for training purposes when each country informs the other.  The impact was an important turning point in Anglo-American and American-Canadian relations. The effect confirmed the permanent U.S. rights to fish off Newfoundland and Labrador. The Convention also provided for Russian mediation on the issue of escaped slaves from British hands (American slave owners eventually received financial compensation) and also established that the border would run from angle Inlet south to forty-ninth latitude, then west to the Rockies. The Oregon Country would remain open to both countries for ten years. A plaque from the Ontario Heritage Trust in Kingston, Ontario, recognizes the Rush Bagot Agreement (44°13′48″N 76°27′59″W / 44.229894°N 76.466292°W / 44.229894; -76.466292). A commemorative plaque is also on the former site of the British Embassy in Washington, D.C (38°54′13.7″N 77°3′8.4″W / 38.903806°N 77.052333°W / 38.903806; -77.052333) where the agreement was negotiated.
On the site of Old Fort Niagara (43°15′48″N 79°03′49″W / 43.263347°N 79.063719°W / 43.263347; -79.063719) is a monument with reliefs of Rush and Bagot as well as the words of the treaty.  The treaty provided for a vast demilitarization of the lakes along the international border, where many British naval agreements and forts remained. The treaty provided that the United States and British North America could each maintain a military ship (no more than 100 tons of load) and a gun (no more than eighteen pounds) on Lake Ontario and Lake Champlain. The remaining Great Lakes allowed the United States and British North America to maintain on the waters two military ships “of the same load” armed with “the same force”. . . .