The Webster–Ashburton Treaty, signed August 9, 1842, was a treaty resolving several border issues between the United States and the British North American colonies. Signed under John Tyler's presidency, it resolved the Aroostook War, a nonviolent dispute over the location of the Maine–New Brunswick border. It established the border between Lake Superior and the Lake of the Woods, originally defined in the Treaty of Paris (1783), reaffirmed the location of the border (at the 49th parallel) in the westward frontier up to the Rocky Mountains defined in the Treaty of 1818, defined seven crimes subject to extradition, called for a final end to the slave trade on the high seas, and agreed to shared use of the Great Lakes.