Cummins Jackson was a paternal uncle of Confederate General Thomas Jonathon "Stonewall" Jackson (1824-1863). He owned and operated a grist mill at Jackson's Mill, Virginia (now West Virginia).

In 1830, 6 year-old Thomas and his younger sister Laura Ann went to live with Cummins Jackson. His brother, Clarksburg attorney Jonathan Jackson (1790-1826) had died of typhoid fever. The children's mother, Julia Neale Jackson (1789-1831), died five years later, leaving her children orphaned.

Young Thomas helped around his uncle's farm, tending sheep with the assistance of a sheep dog, driving teams of oxen and helping harvest the fields of wheat and corn. Formal education was not easily obtained, but he attended school when and where he could. Much of Thomas Jackson's education was self-taught. He would often sit up at night reading by the flickering light of burning pine knots.

The story is told that Thomas once made a deal with one of his uncle's slaves to provide him with pine knots in exchange for reading lessons. This was in violation of a law in Virginia at that time that forbade teaching a slave to read or write, but nevertheless, Jackson taught the man as promised. In his later years at Jackson's Mill, Thomas served as a schoolteacher.

In 1842, young Thomas Jackson was appointed to the United States Military Academy at West Point, New York, and he left Jackson's Mill. He later served in the U.S. Army, was an instructor at Virginia Military Institute, and during the American Civil War, became the right hand of Confederate General Robert E. Lee until he was killed during the war near Chancellorsville, Virginia in 1863.

In modern times, the preserved grist mill of Cummins Jackson is the centerpiece of a historical site and museum at the Jackson's Mill Center for Lifelong Learning and State 4-H Camp. The facility, located in Weston, West Virginia, serves as a special campus for West Virginia University (WVU) and the WVU Extension Service.