Raphael Semmes was born in Charles County, Maryland, on 27 September 1809. Entering the Navy as a Midshipman in 1826, he subsequently studied law and was admitted to the bar while remaining in the service. During the Mexican War, he commanded the brig USS Somers in the Gulf of Mexico. She was lost in a storm off Vera Cruz in December 1846, but Semmes was commended for his actions in that incident. While on extended leave after the war, he practiced law in Mobile, Alabama. Promoted to the rank of Commander in 1855, Semmes was assigned to Lighthouse duties until 1861, when Alabama's secession from the Union prompted him to resign from the U.S. Navy and adhere to the Confederacy.

Appointed a Commander in the Confederate Navy in April 1861, Raphael Semmes was sent to New Orleans to convert a steamer into the cruiser CSS Sumter. He ran her through the Federal blockade in June 1861 and began a career of commerce raiding that is without equal in American naval history. During Sumter's six months' operations in the West Indies and the Atlantic, he captured eighteen merchant vessels and skillfully eluded pursuing Union warships. With his ship badly in need of overhaul, he brought her to Gibraltar in January 1862 and laid her up when the arrival of Federal cruisers made a return to sea impossible.

After taking himself and many of his officers to England, Semmes was promoted to the rank of Captain and given command of the newly-built cruiser CSS Alabama. From August 1862 until June 1864, Semmes took his ship through the Atlantic, into the Gulf of Mexico, around the Cape of Good Hope and into the East Indies, capturing some sixty merchantmen and sinking one Federal warship, USS Hatteras. At the end of her long cruise,Alabama was blockaded at Cherbourg, France, while seeking repairs. On 19 June 1864, Semmes took her to sea to fight the Union cruiser USS Kearsarge and was wounded when she was sunk in action. Rescued by the British yacht Dearhound, he went to England, recovered and made his way back to the Confederacy.

Semmes was promoted to Rear Admiral in February 1865 and commanded the James River Squadron during the last months of the Civil War. When the fall of Richmond, Virginia, forced the destruction of his ships, he was made a Brigadier General and led his sailors as an infantry force. Briefly imprisoned after the conflict, he worked as a teacher and newspaper editor until returning to Mobile, where he pursued a legal career. Raphael Semmes died on 30 August 1877.