Jacob Walker, Alamo defender, was born in Tennessee in 1799. In 1827 he moved to Nachitoches, Louisiana, where he married Sara Ann Vauchere. Their first two children, Monette and Nancy Ann Louisa, were baptized at the Immaculate Conception Church in Nachitoches on December 20, 1828, and August 15, 1830. The couple produced five more children named Robert, Margaret, John, Leonard, and George.
Walker and his wife became unofficial Texans in 1829, but took the citizenship oath the following year. The Walker family settled near Nacogdoches and travelled along the Nacodoches Trail for several years until Jacob sold his Louisiana property on February 11 and March 21, 1831. He worked as a farmer and took part in the siege of Bexar and afterwards remained in Bexar as a member of Capt. William R. Carey's artillery company. Walker joined the Texas Army on November 12, 1835, but it is unclear when he arrived at the Alamo.
Susanna W. Dickinson recalled that, during the siege of the Alamo, Walker often spoke to her about his children. He served as an artillery man during the battle until his cannon was disabled. She also recalled that during the battle, Walker and two other artillerymen rushed into her room pursued by Mexican soldiers who shot and bayonetted him to death as she looked on. Walker was a first cousin of fellow Alamo defender Asa Walker. Following Jacob's death, his wife and family received 1,920 acres of land, and $36.26 for his five months of military service.