In 1821, Mexico won its independence from Spain and ramifications of that historic change was felt in the trans Nueces region, including what would become Duval County. The Spanish state of Nuevo Santander seized to exist and the area between the Rio Grande and Nueces Rivers was now part of the Mexican state of Tamaulipas.
On December 15, 1826 Mexico adopted Decree #42 that laid out new colonization laws. The laws allowed foreigners to colonize vacant lands in the state, provided they submitted to the decrees of the Republic and those of the state. No foreigners took up the Mexican government in the area around Duval County. The nearest such settlement was the McMullen and McGloin grant granted to the Irish in nearby San Patricio.
The decree defined a sitioas a square league or 25 million square varas, a vara being three geometrical feet or about 32 inches. A labor was designated as one million square varasor 1,000 varas on each side of a square.
The congress of Tamaulipas adopted its own land decree on October 28, 1830. In Law No. 47, the congress recognized the advantages that could result from increasing the population in the Nueces territory, considered one of the most fertile areas of the state of Tamaulipas. The lack of population in the area contributed to a lack of security to the pueblos and ranchos on the frontier. The state hoped that the new law would encourage colonizers and landowners, which in turn would enrich the state’s coffers.
Tamaulipas wanted to establish from one to three new settlements on the edge of the Nueces River in lands owned by the state. These new settlements would be exempt for 10 years from all state requirements, except for those imposed by their own town councils and approved by the state legislature.
Any settler residing in or in the vicinity of these towns was free to capture and keep any wild horses for a period of 10 years, under rules prescribed by the towns themselves. Each head of a family would receive a league of free pastureland as prescribed in Article 14 of the Colonization Law. That was in addition to any other land he might be eligible to in the town proper for planting. Any individual who settled in this area with at least 50 families would be entitled to five additional leagues of land apart from the one league that each family would receive.
Each town would get from the state 100 fusiles and the town council would distribute them among the neighboring ranches. Settlers were exempt from military service but were considered an armed militia in defense of Mexican independence, the integrity of their territory and the protection of their towns from the Indian aggressors.
As a result of these new laws, those who had received land grants from the Spanish crown would have to recertify their holdings and those wishing to acquire land would now play under different rules.