In 1718, Bernard de la Harpe was ordered by Louisiana Govenor de Bienville to establish a trading post with the Caddos north of the Great Raft of the Red River. De la Harpe wrote a journal to record his journey as he, his crew, and his Caddo guides made their way through the lakes, marshes, and "inundated prairies" that formed the haunting landscape surrounding the Red River north of Natchitoches. Multiple times, he described going five leagues up the river and realizing that he had only made two leagues of headway due to the twisty nature of the river and its environment.
Eventually, de la Harpe and his men built a wooden trading post at the "abandoned village of the Nassonite chief" in either today's McCurtain County (OK), Bowie County (Texas) or Little River County (AR). Archeologists agree that the post was in Bowie County. According to another source I've found, the Nassonite (a Caddo tribe) village was abandoned prior to de la Harpe's arrival due to a 1702 smallpox outbreak. After the post was built, Frenchmen arrived and formed trading relationships with the Caddos in the area; one of the traders was the family of Francois la Grappe.
De la Harpe's journey was a bit daunting. This excerpt explains it:
[March,1719] "The 14th, we sailed along the high shore a league; then we found some timbers so thick that it seemed incredible to be able to go through them. There was on the branches of these trees and infinite number of snakes, upon which it was necessary for us to fire some musket shots from fear that they might fall into our boats. This route was very painful and fatigued our men extremely. We entered afterwards into a channel full of alligators where the currents were frightful. we passed through it by the tow line and by pulling ourselves from branch to branch; we stopped then on a prairie. The route for the day was north two leagues."
The Nassonite Trading Post remained at the Red River for almost sixty years. By the time the United States purchased Louisiana Territory, it had been abandoned due to disease outbreaks. John Sibley conducted several inquiries with the original families of the post to learn about them (as well as a few other trading posts, such as Fort St. Louis de Carolette and Fort Le Dout). Sibley's interviews with the French settlers warrants another post entirely!