The original name of the Alamo was San Antonio de Valero. It served as a mission used by Spanish Catholic priests from its construction in 1744 to 1793 when it became a fort.
In the 17th and 18th centuries, Texas was part of the Spanish empire. For both religious and political reasons, priests of the Spanish Catholic church began the construction of churches in Texas to convert the Native American population. The purpose of this was not only to spread the Catholic faith but to change the culture of the local people to make them more like the Spanish.
Disease and integration with Spanish immigrants left few Native American converts by the 1790s. San Antonio de Valero was secularized and handed over to the local Spanish government. It was then converted into both a hospital and military post. It was during this time that it became known as "The Alamo," after the hometown of its first garrison, Alamo de Parras. In 1821 Mexico, of which Texas was still a part, declared its independence from Spain. The Alamo was then used as a garrison for Mexican troops until the fort was captured by rebels during the Texas War for Independence in 1836.