The ship was built at the Newport News Shipbuilding Company of Newport News, Virginia, from her keel laying in April 1915, her launching in January 1917, and her commissioning in December that year. She was armed with a battery of twelve 14-inch (356 mm) guns in four three-gun turrets, and was protected by heavy armor plate, with her main belt armor being 13.5 inches (343 mm) thick.
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The ship remained in North American waters during World War I, conducting training exercises to work up the crew. Throughout the 1920s and 1930s, the ship served in the Pacific Fleet. In May 1941, with World War II and the Battle of the Atlantic raging, Mississippi and her two sister ships were transferred to the Atlantic Fleet to help protect American shipping through the Neutrality Patrols. Two days after the Japanese attack on Pearl Harbor, Mississippi departed the Atlantic to return to the Pacific Fleet; throughout her participation in World War II, she supported amphibious operations in the Pacific. She shelled Japanese forces during the Gilbert and Marshall Islands and the Philippines campaigns and the invasions of Peleliu and Okinawa. The Japanese fleet attacked American forces during the Philippines campaign, and in the ensuing Battle of Leyte Gulf, Mississippi took part in the Battle of Surigao Strait, the last battleship engagement in history.
After the war, Mississippi was converted into a gunnery training ship, and was also used to test new weapons systems. These included the RIM-2 Terrier missile and the AUM-N-2 Petrel missile. She was eventually decommissioned in 1956 and sold to ship breakers in November that year.