The Toledo War (1835–1836), also known as the Michigan–Ohio War or Ohio–Michigan War, was a boundary dispute between the U.S. state of Ohio and the adjoining territory of Michigan over what is now known as the Toledo Strip. Control of the Maumee River's mouth and the inland shipping opportunities it represented, and the good farmland to the west, were seen by both parties as valuable economic assets.
Poor geographical understanding of the Great Lakes helped produce conflicting state and federal legislation between 1787 and 1805, and varying interpretations of the laws led the governments of Ohio and Michigan to both claim jurisdiction over a 468-square-mile (1,210 km2) region along their border.