I think it was Stephen F. Austin. I'm not certain he was first, but I know he was most successful.
The Texas territory
Stephen Austin was the first American impresario to bring settlers to Texas. He was loyal the the Mexican government until Santa Anna voided the Mexican Constitution and pronounced himself dictator.
He took the first group of settlers to Texas to settle.
Gorge Washington
Because they allowed American settlers to populate these lands, in the first place.
I believe texas was a Spanish colony.
La Salle.
The first American settlers arrived in San Juan in 1859.
The first settlers were 56 iindividuals in 15 families from the Canary Islands.
La Salle.
because they felt like it
To seek new missions