six months later he was shot and killed by a guard – reportedly bribed to do so by José Félix Trespalacios, thus ending the Long Expeditions. Mexican Texas Along with the rest of Mexico, Texas gained its independence from Spain in 1821 following the Treaty of Córdoba, and the new Mexican state was organized under the Plan of Iguala, which created Mexico as a constitutional monarchy under its first Emperor Agustín de Iturbide. During the transition from a Spanish territory to a part of the independent country of Mexico, Stephen F. Austin led a group of American settlers known as the Old Three Hundred, who negotiated the right to establish colonies of settlers in Texas with the Spanish Royal governor of the territory, and to bring their slaves with them. These colonies were limited in quotas and to specific locations. Since Mexican independence had been ratified by Spain shortly thereafter, Austin later traveled to Mexico City to secure the support of the new country for his right to settle. The establishment of Mexican Texas coincided with the Austin-led settlement, leading to animosity between Mexican authorities and ongoing American settlement of Texas. The First Mexican Empire was short-lived, being replaced by a republican form of government in 1823. In 1824, the sparsely populated territories of Texas and Coahuila were joined to form the state of Coahuila y Tejas. The capital was controversially located in southern Coahuila, the part farthest from Texas. Following Austin's lead, additional groups of settlers, known as Empresarios, continued to colonize Mexican Texas from the United States. A spike in the price of cotton, and the success of plantations in Mississippi encouraged large numbers of white Americans to migrate to Texas and obtain slaves to try to replicate the business model. In the Law of April 6, 1830, Mexican President Anastasio Bustamante outlawed American immigration to Texas, following several conflicts with the Empresarios over the status of slavery, which had been abolished in Mexico in 1829, but which the Texians refused to end. Texians replaced slavery with long-term indentured servitude contracts signed by "liberated" slaves in the United States to work around the abolition of slavery. Angered at the interference of the Mexican government, the Empresarios held the Convention of 1832, which was the first formal step in what became the Texas Revolution. Texas Revolution By 1834, the American settlers in the area outnumbered Mexicans by a considerable