Le Poste des Cadodaquious, a small French fort northwest of Texarkana in what is now Bowie County, was founded in 1719 by Bénard de La Harpe as a part of his land concession. The founding was an opportunistic military advance in an area where the Spanish had made similar advances. La Harpe built his stockaded post on the south bank of the Red River near a village of the Nasoni Indians, a Caddoan group who were part of the Hasinai Confederacy. Consequently, the fort was sometimes called Le Poste des Nassonites, for Nasoni Indians, or, more commonly, Le Poste des Cadodaquious, reflecting the French pronunciation of Kadohadacho, a name used by various Caddoan peoples to describe themselves and their homeland. Recent analysis of source material and subsequent related records for the area suggests that the site was on the escarpment near the present site of Everett or Barkman. La Harpe was the fort's first commandant. After his departure in late 1719 the post was garrisoned by a sergeant's detachment from Natchitoches, Louisiana, and Louis Juchereau de St. Denis succeeded La Harpe in command.
The trader and interpreter Alexis Grappé was important at the fort. The post had little military significance except in limiting the northward influence of the Spanish and serving as a French station for trade. In 1719 Durivage and Mustel explored the Red River from the post. Later, La Harpe moved on to the northwest and came into contact with various Wichita groups, probably along the lower Canadian River, thereby laying the ground for years of French trade in the region. Early trade ventures involving Francis Harvey (Herve) extended westward to the Kiamichi and Boggy rivers and to the Pani Piques, or Taovoya Indians, after their removal to the Red River around 1757. The post was a supply base for the expeditions of Fabry de La Bruyere in 1742 and Pierre A. Mallet in 1750. Jean Baptiste Brevel left the post for Santa Fe in 1767.
A small French settlement developed close to the fort from its earliest days. At least two of Grappé's children, François and Mary Pulogia, and Jean Baptiste Brevel were born there. The French abandoned the post shortly after the Louisiana cession. In 1770 Athanase de Mézières attempted to reestablish the post for the Spanish under the name San Luiz de los Cadodachos. The Nasonis deserted their ancestral home shortly thereafter. Archeological studies of Nasoni gravesites have revealed a variety of French trade goods. Thomas Freeman (see CUSTIS, PETER), although aware of the vicinity, failed to locate the fort in 1806. The name Fort St. Louis de Carloretto is an American misnomer.