John Osborne and James W. Gerencser, eds., “Marcus Lafayette Gordon,” Dickinson Chronicles, http://chronicles.dickinson.edu/encyclo/g/ed_gordonML.htm.
The Civil War broke out soon after. On September 25, 1861, Gordon mustered into what was to become Company A, or the "Prairie Rovers," of the Eighth Texas Cavalry Regiment. This unit was popularly known as "Terry's Texas Rangers," although they were not technically state rangers. Gordon was elected as a third lieutenant and won promotions up to captain. He showed a proficiency for scouting missions and led "Gordon's Scouts" in 1863 as part of Wharton's Brigade. Gordon was seriously wounded at Shiloh in the Fallen Timbers charge on April 8, 1862, and the bullet was never removed. For some reason, records indicate that he ended the war once again with the rank of third lieutenant. Gordon returned to Lawrenceville, not Waco, and took up teaching for several years before entering business in the town. He operated a merchant company, Spence and Gordon, in partnership with J. D. Spence. The company was prospering at the time of Gordon's death.
In January 1868, Gordon married Kate Maltbie of Lawrenceville. The couple had three daughters: Mary, Hallie, and Clara. All three were born in Lawrenceville. In spring 1874, Gordon suffered a flare-up of infection above the hip at the site of his war wound. After a two-week illness, Marcus Lafayette Gordon died on April 28, 1874. He was thirty-seven years old.