Thomas Hoomes Williamson was born August 30, 1813 in Richmond, Virginia, the son of Thomas and Anne Walke Williamson. He spent most of his childhood in Norfolk, Virginia, where he received his early schooling. He entered the United States Military Academy at West Point in 1829, but resigned in 1833 before receiving his degree. In 1834 entered the profession of Civil Engineering and was the assistant to the U. S. Engineer in charge of building the dry dock in the Norfolk Navy Yard. Williamson married Louisa Henrietta Fenton Garnett on May 11, 1837. The couple had five children before Louisa died in 1859-- Mercer, William, Anne, Thomas, and Olympia.

In 1841, Williamson accepted a faculty appointment at the Virginia Military Institute in Lexington, where he was to spend the remainder of his career except for a brief absences during the Civil War. He taught tactics, drawing, and engineering, and at various times was assigned additional duties (Commandant of Cadets, Treasurer, Librarian). While at VMI he wrote a text book, , for use by his students.

Williamson took on various special assignments during the Civil War. In April 1861 he served with the Confederate Engineers Corps and worked on the defenses of the Rappahannock River and Manassas. In October of that year, he was ordered to return to VMI to teach Civil and Military Engineering, but he was recalled to the Confederate Army in April 1862 for temporary special duty on the staff of General Stonewall Jackson. In 1864 Williamson married for the second time. His new wife was a widow, Mrs. Julia Wharton (nee Lewis) of Lexington. She was the mother of his two youngest children--Sydney Bacon, and Cornelia.

Williamson continued his teaching career at VMI until shortly before his death on March 31, 1888. He is buried in the Stonewall Jackson Cemetery in Lexington.