Walpole Island is an island in southwestern Ontario, Canada on the border between Ontario and Michigan in the United States. It is located in the mouth of the St. Clair River on Lake St. Clair, approximately 30 miles (50 km) northeast of Detroit, Michigan, and Windsor, Ontario. It is unceded territory and is inhabited by the Chippewa, Potawatomi, and Ottawa people. Tecumseh's grave is on the reserve there.