The siege of the Alamo (February 23 – March 6, 1836) was the first thirteen days of the Battle of the Alamo. On February 23, Mexican troops under General Antonio Lopez de Santa Anna entered San Antonio de Bexar, Texas, and surrounded the Alamo Mission. The Alamo was defended by a small force of Texians and Tejanos, led by William Barrett Travis and James Bowie, and included Davy Crockett. Before beginning his assault on the Alamo, Santa Anna offered them one last chance to surrender. Travis replied by opening fire on the Mexican forces and, in doing so, effectively sealed their fate. The siege ended when the Mexican Army launched an early-morning assault on March 6. Almost all of the defenders were killed, although several civilians survived.