Colonel Martin was the commanding field officer of the Seventeenth Regiment of North Carolina Infantry. They first assembled as the Seventh Volunteers at Plymouth in June of 1861. He was captured at Fort Hatteras in 1861 and was a prisoner of war at Fort Warren in Boston. Before and after the war, Martin was a lawyer from Elizabeth City. His brother, James, was a Confederate Brigadier General. Many of William's business papers are collected at the Wilson Library at the University of North Carolina at Chapel Hill. William attended the University of North Carolina before becoming a civic leader of Elizabeth City and Albemarle County. He ran for Congress in 1851 and was a vestryman of Christ Episcopal Church.