There are two potential explanations. Spanish authorities established the Mission San Antonio de Valero in 1718 and construction continued over the next several decades. Following secularization in 1793, a company of Spanish soldiers from San Carlos del Alamo de Parras in Coahuila used the buildings as its headquarters. The soldiers referred to their post as the Alamo and applied the name to their new assignment. Another explanation for the name refers to the Alamo (cottonwood) trees growing along the stream banks there.