Samuel Willis Tucker Lanham was born in 1846 in South Carolina to James Madison and Louisa de Aubrey (Tucker) Lanham in Spartanburg District (now County), South Carolina, and named for his maternal grandfather, Samuel Willis Tucker. When the Civil War began, Lanham volunteered for the Confederate States Army, despite the fact that he was only fifteen years old. He fought primarily in Virginia, was wounded at the Battle of Spotsylvania Court House, and after hostilities ended he married. He and his wife settled in Weatherford, Texas, where he worked and studied law.