b. 1815 – New Orleans
Governor: March 1861–November 1861

Clark studied law and was admitted to the bar in Alabama. He received a citation for bravery for his military service in the U.S.-Mexican War, and served in the Texas House and Senate, and as secretary of state and state commissioner of claims under Pease. He was elected lieutenant governor in 1859.

Clark became governor after the Secession convention declared the governor’s office vacant because Sam Houston refused to take the oath of allegiance to the Confederacy. He worked with Confederate authorities to get army supplies and raised poll taxes and ad valorem taxes to help stabilize state finances. After a defeat by Francis R. Lubbock in a close race for a full term, he joined the Confederate Army. He fled to Mexico after the war but later returned home to Marshall.