Stephen F. Austin, the first "legitimate" American colonizer to Mexican Texas, resided in Hempstead County, Arkansas for a brief while after 1819. By 1822, he was busy trying to realize his now-deceased father's empressario with the newly formed Mexican government. To understand his venture, Stephen F. Austin traced a Mexican map of the Province of Texas from 1818 and painted it with water colors.
Of course, I'm focusing on the Red River portion of the map, noted here as the Rio Colorado de Natchitoches. Austin didn't draw the entire river because the borders between Texas and Indian Territory were still relatively undefined. Notice that the northeastern boundary of the province follows the Index Line along longitude 18 (Washington), as per the Treaty of 1819.
Pecan Point (Punta apecon) is placed on the southern bank of the Red River, while American maps placed it on the north shore of the river, because Americans weren't supposed to be in Spain/Mexico. Further east of Pecan Point is a Caddo village, possibly where today's Texarkana is located. Below Pecan Point is a substantial village of the Quichais, a Wichita tribe who settled along the Trinity River. East along the trading path designated as the Comanche Trail (Camino des Comanches), and north of Nacogdoches, is the village of the Texas people. East of this village is another one, but I can't decipher the name. What do you think it is?
By the way, this Comanche Trail is not the one that was later identified in western Texas. This trail was probably not used by Comanches but was an indicator that it went west towards their territory, a trading path, or an error; it may have been a Caddoan path instead.
To see this fantastic map in full, go here: https://www.loc.gov/item/98687158/