On December 9,1835, the Texan Army, fighting a war for independence against Mexico, took possession of the city of San Antonio. During the early 1800s, Texas was part of Mexico. When Santa Ana overthrew the Mexican government and established himself as dictator, an American named Benjamin Rush Milam created the Texan army and helped establish the Republic of Texas. Texas remained a republic until February 19, 1846, when it became part of the United States.