In February 1836, Cos returned to San Antonio with Santa Anna and led a column of 300 soldiers in the siege of the Alamo. His men assaulted the northwest corner of the mission on March 6, eventually overrunning the north wall. On April 21, Cos arrived with over 500 reinforcements for Santa Anna shortly before the Battle of San Jacinto. That afternoon Texian forces led by General Sam Houston decisively defeated Santa Anna's army in a battle which lasted only eighteen minutes. Cos and Santa Anna both escaped during the battle; Santa Anna was captured the next day, on April 22, and Cos was captured on April 24. General Santa Anna subsequently surrendered his army and eventually all Mexican claims to Texas, ending the Texas Revolution.