Benjamin moved to Grayson Co TX about 1854, following his father. He resided in Collin Co TX in 1880. He served as a Private in Co D, 1st Battalion, of the TX Sharp Shooters in the Civil War. He also served in the Texas Rangers and was a U.S. Deputy Marshall. He married (1) his cousin Rebecca Flynn Poindexter who died 17 Sep 1866. They had no children. He married (2) Amanda Frances Cartwright on 1 Nov 1868 in Grayson Co TX and they had 11 children.
In September of 1901, Amanda F. Poindexter stated her husband had died two years previously at the age of 64 and that they were married 1868, in Grayson Co, TX.
Benjamin Speer Poindexter's widow and children registered in the Five Civilized Tribes enrollment in 1896.
Benjamin Speer POINDEXTER and Rebecca Flynn POINDEXTER were married. Rebecca Flynn POINDEXTER301, daughter of Zadock Wright POINDEXTER and Sarah Jane "Sallie" ANDERSON, was born on 25 January 1846 in Dade County, Missouri.301 She died on 17 September 1866 at the age of 20 in Grayson County, Texas.301
Married her cousin Benjamin Speer Poindexter. No children.
Buried White Mound Cemetery.