Born in Williamson County, Tennessee, in 1827, Robert E. Neill migrated with his family to what is now Caldwell County, Texas, at the age of four. At age nine, while grinding corn meal for the Texas army, he suffered a crushing injury that crippled his left arm. Despite this, he went on to serve in the U.S. Army in 1847, during the war with Mexico. Afterward he was a rancher but volunteered with the Texas Rangers and other units, as needed. His military career concluded with service to the confederacy in the Civil War. Neill retired to his ranch and family. He and his wife, Elizabeth, had five children, and spent their remaining years on their property in Atascosa County. Robert died in 1878.