Neutral Strip in Louisiana Territory

An 1814 map of Louisiana showing the Neutral Ground. Louisiana State Museum

After the Louisiana Purchase was completed between France and the United States in December 1803, the United States and Spain were unable to agree on the boundary between Louisiana Territory and Texas. In order to avert an armed clash, Gen. James Wilkinson and Lt. Col. Simón de Herrera, the American and Spanish military commanders respectively entered into an agreement declaring the disputed territory Neutral Ground on November 5, 1806.

The boundaries of the Neutral Ground were never officially described beyond a general statement that the Arroyo Hondo on the east and the Sabine River on the west were to serve as boundaries. It may be safely assumed, however, that the Gulf of Mexico constituted the Southern boundary and the 32nd parallel of latitude formed the northern boundary.

Although it had been stipulated in the agreement that no settlers would be permitted in the Neutral Ground, settlers from both Spanish and American territory moved in, along with runaway slaves, army deserters, and criminals. The two governments were compelled to send joint military expeditions in 1810 and 1812 to expel outlaws who were making travel and trade in the neutral strip dangerous and unprofitable. Ownership of the strip went to United States by the Adams-Onís Treaty in 1821.