Theodore M. Brantley (or Brantly) (February 12, 1851 – September 16, 1922) was the longest-serving Chief Justice of the Montana Supreme Court, serving for 23 years (1899–1922). Brantley was born near Lebanon, Tennessee. He came from a political family in Tennessee—two of his mother's brothers were elected governor of Tennessee (Neill S. Brown in 1847, John C. Brown in 1871).Brantley was educated at Southwestern Presbyterian University in Clarksville, Tennessee and the law school of Cumberland University in Lebanon, graduating in 1881. After practicing law for several years, Brantly became a professor of Ancient Languages, first at Illinois College and then at the College of Montana in Deer Lodge. After returning to the practice of law for several years, Brantley was elected District Judge