Her keel was laid down 24 April 1917 by Newport News Shipbuilding Company of Newport News, Virginia. She was launched on 20 March 1920 sponsored by Mrs. E. Brook Lee, wife of the Comptroller of the State of Maryland and commissioned on 21 July 1921 with Captain C.F. Preston in command.
With a new type of seaplane catapult and the first 16 inch (406 mm) guns mounted on a U.S. ship, Maryland was the pride of the Navy. Following an east coast shakedown she found herself in great demand for special occasions. She appeared at Annapolis, Maryland, for the 1922 United States Naval Academy graduation and at Boston, Massachusetts, for the anniversary of Battle of Bunker Hill and the Fourth of July. Between 18 August and 25 September she paid her first visit to a foreign port transporting Secretary of State Charles Evans Hughes to Rio de Janeiro for Brazil's Centennial Exposition. The next year, after fleet exercises off the Panama Canal Zone, Maryland transited the canal in the latter part of June to join the battle fleet stationed on the west coast.
She made a goodwill voyage to Australia and New Zealand in 1925, and transported President-elect Herbert Hoover on the Pacific leg of his tour of Latin America in 1928. The eight 3" anti-aircraft guns were replaced by an equal number of 5"/25 caliber guns in 1928-1929. Throughout these years and the 1930s she served as a mainstay of fleet readiness through tireless training operations. In 1940 Maryland and the other battleships of the battle force changed their bases of operations to Pearl Harbor. She was present at battleship row along Ford Island during the Japanese attack on Pearl Harbor on 7 December 1941.
Seaman Leslie Short, addressing Christmas cards near his machine-gun, brought the first of his ship's guns into play, shooting down one of two torpedo planes that had just released against . Inboard of Oklahoma, and thus protected from the initial torpedo attack, Maryland managed to bring all her antiaircraft batteries into action. Maryland was struck by two armor-piercing bombs which detonated low-order. The first struck the forecastle awning and made a hole about 12 feet by 20 feet. The second exploded after entering the hull at the 22-foot water level at frame 10. The latter hit caused flooding and increased the draft forward by five feet. Maryland continued to fire and, after the attack, sent firefighting parties to assist her sister ships. The Japanese announced that she had been sunk, but 30 December, battered yet sturdy, the ship entered the repair yard at Puget Sound Navy Yard. Two of the original twelve 5"/51 caliber guns were removed and the 5"/25 caliber guns were replaced by an equal number of 5"/38 caliber guns.
She emerged 26 February 1942 not only repaired but modernized and ready for service. During the important Battle of Midway, the old battleships, not fast enough to accompany the carriers, operated as a backup force. Thereafter Maryland engaged in almost constant training exercises until 1 August, when she returned to Pearl Harbor.
Assigned sentinel duty along the southern supply routes to Australia and the Pacific fighting fronts, Maryland and Colorado operated out of the Fiji Islands in November and advanced to the New Hebrides in February 1943. Her return to Pearl Harbor after ten months in the heat of the South Pacific brought the installation of additional 40 mm antiaircraft protection.
In the vast amphibious campaigns of the Pacific the firepower of Maryland and her sister ships played a key role. Departing the Hawaiian Islands on 20 October for the South Pacific, Maryland became flagship for Rear Admiral Harry W. Hill's Southern Attack Force in the Gilbert Islands Invasion, with Major General Julian C. Smith, Commander, Second Marine Division, embarked. Early on 20 November her big guns commenced five days of shore bombardment and call fire assignment in support of one of the most gallant amphibious assaults in history, at Tarawa. After the island's capture, she remained in the area protecting the transports until she headed back to the United States 7 December.
Maryland steamed from San Pedro, California, on 13 January 1944, rendezvoused with TF 53 at Hawaii, and sailed in time to be in position off the well-fortified Kwajalein Atoll in the Marshall Islands on the morning of 31 January. Assigned to reduce pillboxes and blockhouses on Roi Island, the old battleship fired splendidly all day and again the following morning until the assault waves were within 500 yards of the beach. Following the operation she steamed back to Bremerton, Washington, for new guns and an overhaul.
Two months later Maryland, again readied for battle, sailed westward 5 May to participate in the biggest campaign yet attempted in the Pacific war -- Saipan. Vice Admiral R.K. Turner allotted TF 52 three days to soften up the island before the assault. Firing commenced 0545 on 14 June. Silencing two coastal guns, Maryland encountered little opposition as she delivered one devastating barrage after another. The Japanese attempted to strike back through the air. On 18 June the ship's guns claimed their first victim but four days later a G4M Betty sneaked in flying low over the still-contested Saipan hills and found two anchored battleships. Crossing the bow of Pennsylvania, she dropped a torpedo which opened a gaping hole in Maryland's bow, portside. Casualties were light and in 15 minutes she was underway for Eniwetok, and shortly thereafter to the repair yards at Pearl Harbor.
With an around-the-clock effort by the shipyard workers, on 19 August, 34 days after arrival, the ship again steamed forth for the war zone. Rehearsing briefly in the Solomons, she joined Rear Admiral J. B. Oldendorf's Western Fire Support Group (TG 32.5) bound for the Palau Islands. Firing first on 12 September to cover minesweeping operations and underwater demolition teams, she continued the shore bombardment until the landing craft approached the beaches on 15 September. Four days later organized resistance collapsed, permitting the fire support ships to retire to the Admiralty Islands.
Reassigned to the Seventh Fleet, Maryland sortied 12 October to cover the important initial landings in the Philippines at Leyte. Despite floating naval mines, the invasion force entered Leyte Gulf on 18 October. The bombardment the following day and the landings of 20 October went well, but the Japanese decided to contest this success with both kamikazes and a three-pronged naval attack.
Forewarned by submarines and scout planes, the American battleship-cruiser force steamed 24 October to the southern end of Leyte Gulf to protect Surigao Strait. Early on 25 October the enemy battleships Fusō and Yamashiro led the Japanese advance into the Strait. The waiting Americans pounded the enemy ships severely. First came torpedoes from the fleeting PT boats, then more torpedoes from the destroyers, which destroyed the battleship Fusō. Next came gunfire from the cruisers. Finally, at 0355 the readied guns of the battleship line opened fire. Thunderous salvos of heavy caliber fire slowed the enemy force and set the Japanese battleships on fire. Leaving their doomed battleships behind, the decimated enemy ships fled; only a remnant of the original force escaped subsequent naval air attacks. Similarly other U.S. forces blunted and repulsed attacks by the center and northern enemy forces during the decisive Battle of Leyte Gulf.
In the aftermath of this important victory, Maryland patrolled the southern approaches to Surigao Strait until 29 October; after replenishment at Manus, Admiralties, she resumed patrol duty 16 November. Japanese air attacks continued to pose a definite threat. During a raid on 17 November, guns of TG 77.2 splashed 11 of the attacking planes. Shortly after sunset two days later, a determined suicide plane dove through the clouds and crashed onto Maryland between turrets Nos. 1 and 2. Thirty-one sailors died in the explosion and fire that followed. On 29 November, Maryland was again damaged by a kamikaze attack; however, the sturdy battleship continued her patrols until relieved 2 December. She reached Pearl Harbor on 18 December and during the next two months workmen repaired and refitted "Fighting Mary."
After refresher training, Maryland headed for the western Pacific 4 March 1945, arriving Ulithi on 16 March. There she joined Rear Admiral M.L. Deyo's TF 54 and on 21 March departed for the invasion of Okinawa. She closed the coast of Okinawa 25 March and began hitting assigned targets along the southwestern part of the Japanese island fortress. In addition, she provided fire support during a diversionary raid on the southeast coast drawing enemy defenses from the main amphibious landings on the western beaches. On 3 April she received a fire support call from Minneapolis (CA-36). The cruiser was unable to silence entrenched shore batteries with eight inch (203 mm) fire and called on "Fighting Mary's" mighty 16 inch (406 mm) guns for aid. The veteran battleship hurled six salvos which destroyed the enemy artillery.
Maryland continued fire support duty until 7 April when she sailed with TF 54 to intercept a Japanese surface force to the northward. These ships, including the mighty Yamato, came under intense air attacks that same day, and planes of the Fast Carrier Task Force sank six of ten ships in the force. At dusk on the 7th Maryland took her third hit from enemy planes in ten months. A suicide plane loaded with a 500 pound (230 kg) bomb crashed the top of Turret No. 3 from starboard. The explosion wiped out the 20 mm mounts, causing 53 casualties. As before, however, she continued to hit enemy shore positions with 16 inch (406 mm) fire. While guarding the western transport area on 11 April, she splashed two planes during afternoon raids.
On 14 April Maryland left the firing line as escort for retiring transports. Steaming via the Mariana Islands and Pearl Harbor, she reached the Puget Sound Navy Yard at Bremerton, Washington, on 7 May the next day for extensive overhaul. All 5-inch guns were removed and replaced by sixteen 5"/38 caliber guns in new twin mounts. Completing repairs in August, she now entered Operation Magic Carpet fleet. During the next four months she made five voyages between the west coast and Pearl Harbor, returning more than 8,000 combat veterans to the United States.
On 2 June 1961 the Honorable J. Millard Tawes, Governor of Maryland, dedicated a lasting monument to the memory of the venerable battleship and her fighting men. Built of granite and bronze and incorporating the bell of "Fighting Mary," this monument honors a ship and her men whose service to the Nation reflected the highest traditions of the naval service. This monument is located on the grounds of the State House, Annapolis, Maryland.