While himself opposing secession, he raised the Adams County cavalry troops, when war broke out, riding with them to Richmond, Virginia, the new Confederate States of America capitol.

During the Seven Days Battles, Martin's men primarily participated in raids on Union supply lines north of the Chickahominy River.

During the Northern Virginia Campaign, Martin and his legion were left in the vicinity of Richmond to watch McClellan's departing army, and was assigned to the cavalry brigade of Wade Hampton III.

Martin is notable for opposing the Mississippi Constitution of 1890, ending black suffrage, being one of three delegates refusing to sign it.

One of America's first black Congressmen, John R. Lynch, praised Martin in his memoirs for "reflecting the sentiments and respecting the wishes of the dominant and better element of the people of his county."

Martin also served as a primary source on the Forks of the Road slave market for historian Frederic Bancroft.