The Battle of the Alamo was fought in February and March 1836 in San Antonio, Texas. The conflict, a part of the Texas Revolution, was the first step in Mexican President Antonio Lopez de Santa Anna's attempt to retake the province of Texas after an insurgent army of Texian settlers and adventurers from the United States had driven out all Mexican troops the previous year. Mexican forces began a siege of the Texian forces garrisoned at the Alamo Mission on Tuesday, February 23. For the next twelve days, Mexican cannons advanced slowly to positions nearer the Alamo walls, while Texian soldiers worked to improve their defenses.
Benson John Lossing, ed. Harper's Encyclopedia of United States History (vol. 9) (New York, NY: Harper and Brothers, 1912)