Spain had been concerned for many years with what it viewed as the encroachment of the French from Louisiana into Texas. About 1734, the French moved their post at
Natchitoches from the east to the west side of the
Red River. The Spanish governor of Texas,
Manuel de Sandoval, was reprimanded for not protesting this violation of what Spain believed was its sovereign territory. In 1740, Governor
Prudencio de Orobio y Basterra was ordered to investigate French intrusion in the Natchitoches area. Other investigations were ordered in 1744 and 1751. In 1753, Texas Governor
Jacinto de Barrios y Jáuregui determined that the French had encroached on Texas by occupying territory to the west of
Arroyo Hondo, a small creek in western
Natchitoches Parish that had previously been used by the French as their western boundary with Texas. In 1764, the boundary dispute became temporarily moot when France
ceded its Louisiana colony to Spain. This colony was the large area west of the Mississippi River but drained by the same, plus New Orleans and its immediate vicinity. The transfer was made without resolving the earlier border dispute, which did not seem significant under the circumstances. Spain administered the area from
Havana, contracting out governing to people from many nationalities as long as they swore allegiance to Spain and promised to publicly worship in Catholic churches. Many Americans took advantage of these grants that would eventually become known as Rio Hondo claims. By the secret
Third Treaty of San Ildefonso of October 1, 1800, Louisiana was formally transferred back to France, although the Spanish continued to administer it. The terms of the treaty did not specify the boundaries of the territory being returned. Rumors of the treaty reached U.S. President
Thomas Jefferson, who sought to purchase land at the mouth of the Mississippi to ensure American access to the Gulf of Mexico. Jefferson discovered that
Napoleon was willing to sell the entire territory to help fund his wars in Europe. France took formal control of Louisiana from Spain on November 30, 1803, and turned over New Orleans to the United States on December 20, 1803. The U.S. took over the rest of the territory on March 10, 1804. The
Louisiana Purchase doubled the size of the United States and opened U.S. expansion west to the Pacific Ocean and the Gulf Coast. == The boundary dispute between Spain and the United States ==