Franklin B. Sexton was born in New Harmony, Indiana, on April 29, 1828, to Samuel Sexton. The family moved to San Augustine, Texas, in 1838, and his father died around 1841. Sexton received his education from the local Methodist academy before opening his legal practice in San Augustine around 1848. He married Eliza Richardson in 1852, and the couple had twelve children. Sexton joined the Democratic Party and served as president of the Texas State Democratic Convention in 1860. He sided with the Confederacy during the Civil War and secured a seat in the Confederate Congress. He was re-elected in 1863 and remained in Congress until the end of the war. After the war, Sexton reopened his legal practice. He served as a delegate to the 1876 Democratic National Convention, where he ardently supported Samuel J. Tilden. He died on May 15, 1900.