After Mexican independence much of northern Mexico, infact most of many parts of Mexico, were devastated and sparsly populated. These northern areas were hard to defend against both indian incursions and anglo land poaching. Mexico had a just fear that the US was eyeing their northern states. Mexico lacked the people, resources, and equipment to settle these northern areas, so they decided they should try to encourage first foreign (non-us settlements) but when they failed they tried Anglo (US) settlements but to ensure loyalty they would make these Anglos catholic and swear to obey the laws of Mexico. Obviously this backfired as the anglo's loyalty remained with their former home rather than Mexico.
"Economically, the country faced devastation in 1821. It stood in marked contrast to the rich colony that had promised great potential towards the end of the colonial era. Money barely circulated. Once-rich mines struggled to regain their former efficiency. Ranches and farms were no longer productive...An equally urgent concern for the young country was guarding its far northern possessions from United States expansion; Texas was especially vulnerable to encroachment from that country, and colonization offered the best deterrent. But Mexico lacked the strength of population numbers to settle the north."
Economically, the country faced devastation in 1821. It stood in marked contrast to the rich colony that had promised great potential towards the end of the colonial era. Money barely circulated. Once-rich mines struggled to regain their former efficiency. Ranches and farms were no longer productive...An equally urgent concern for the young country was guarding its far northern possessions from United States expansion; Texas was especially vulnerable to encroachment from that country, and colonization offered the best deterrent. But Mexico lacked the strength of population numbers to settle the north.
https://tshaonline.org/handbook/online/articles/npm01
Also Indian raids were a very serious concern and vast swaths of Texas were unsafe for habitation because of the raids. If you look at maps of the time, Indians controlled almost the entire Western half of Texas. Mexico hoped settlements would help deter the raids. Where as something like 40-50% of the indiansIndians in California became christianChristian, this was not the case in Texas.
"After the 1819 Adams-Onís Treaty defined the U.S.-Mexico boundary, Spain began actively encouraging Americans to settle their northern province. Texas was sparsely settled, and the few Mexican farmers and ranchers who lived there were under constant threat of attack by hostile Indian tribes, especially the Comanche, who supplemented their hunting with raids in pursuit of horses and cattle.
To increase the non-Indian population in Texas and provide a buffer zone between its hostile tribes and the rest of Mexico, Spain began to recruit empresarios."
After the 1819 Adams-Onís Treaty defined the U.S.-Mexico boundary, Spain began actively encouraging Americans to settle their northern province. Texas was sparsely settled, and the few Mexican farmers and ranchers who lived there were under constant threat of attack by hostile Indian tribes, especially the Comanche, who supplemented their hunting with raids in pursuit of horses and cattle.
To increase the non-Indian population in Texas and provide a buffer zone between its hostile tribes and the rest of Mexico, Spain began to recruit empresarios.
http://cnx.org/contents/_8trGL3L@4/Independence-for-Texas
Also remember Texas, especially south Texas and the Llano Estacado are not very hospitable places and so encouraging Mexican immigration there was difficult. Especially when there were better spots that were open because of the depopulation caused by the civil wars.
