Texans and fighting men from all over were challenged by an invasion by Mexican Dictator Santa Ana. They responded to Texas General Sam Houston's call to arms to defend Texas from sure destruction if the Alamo was taken by the 5,000 strong Mexican army. These bravest of the brave men forced the huge army to retreat 2 times with their cannons and sure shot rifles from the Alamo walls. The men at the Alamo were killed but the battle of San Jacinto determined the fate of any further rule over Texas by Santa Ana, thus validating Texas as a Republic in 1836. Texas became a state in 1845.