A map of the American Northwest Territory showing the boundary developments in 1790, 1800, and 1810. The upper left map shows the territory acquired by the United States from Britain after the Revolutionary War as established by the Treaty of Paris (1763), including the Territory Northwest of the Ohio River, English possessions to the north of the Great Lakes, Spanish possessions west of the Mississippi River, Virginia south of the Ohio River, the Connecticut Reservation, and the Virginia Military Reservation. The upper right map shows the territory in 1800, with the Northwestern Territory in the eastern half of the Michigan Peninsula, Indiana Territory in the western half, and Kentucky south of the Ohio River (1792). The lower map shows the territory in 1810, with the Indiana Territory reduced to the Upper Peninsula of Michigan and south of Michigan, the Michigan Territory (1805), the Illinois Territory (1809), the Ohio Territory (1802), and the Louisiana Territory west of the Mississippi (1806).