USS Iowa was a pre-dreadnought battleship built for the United States Navy in the mid-1890s. The ship was a marked improvement over the previous Indiana-class battleships, correcting many of the defects in the design of those vessels. Among the most important improvements were significantly better seaworthiness owing to her greater freeboard and a more efficient arrangement of the armament. Iowa was designed to operate on the high seas, which had been the impetus to increase the freeboard. She was armed with a battery of four 12-inch (305 mm) guns in two twin-gun turrets, supported by a secondary battery of eight 8-inch (203 mm) guns.

Upon entering service in June 1897, Iowa conducted training operations in the Atlantic Ocean before moving to the Caribbean in early 1898 as tensions between the United States and Spain over Cuba grew, leading to the Spanish–American War. The ship took part in the bombardment of San Juan, Puerto Rico, and then participated in the blockade of Cuba during the war, and after the Spanish cruiser squadron was found in Santiago de Cuba, she patrolled off the harbor to block their escape. In the Battle of Santiago de Cuba on 3 July, Iowa assisted in the destruction of three of the four Spanish cruisers. After the war, Iowa spent the next several years conducting routine training exercises, serving with the Pacific Squadron from 1898 to 1902, the South Atlantic Squadron until 1904, and the North Atlantic Squadron until 1906, when the latter two units were merged to form the Atlantic Fleet.

Iowa was modernized between 1908 and 1910; she thereafter served as a training ship for naval cadets from the United States Naval Academy and for naval militia crews. Removed from service in 1913 and decommissioned in 1914, she was reactivated after the United States entered World War I in April 1917, initially serving as a receiving ship and then as a training vessel and guard ship. She was decommissioned again in 1919, renamed Coast Battleship No. 4, and converted into a radio-controlled target ship. She was used in bombing experiments off the Virginia Capes in 1921 before being sunk as part of Fleet Problem I off the coast of Panama in March 1923 by the battleship USS Mississippi.

In the early 1880s, the United States Navy began to grapple with the question of coastal defense; the United States at that time had a significant isolationist streak and naval strategy had historically been grounded in commerce raiding. After building the interim armored vessels USS Texas and Maine, the navy requested funding for additional ships in 1887, and one vessel was authorized for the following year. Conflicting ideas about the vessel that would be built delayed construction and led the Secretary of the Navy, Benjamin F. Tracy, to convene a Policy Board in January 1890. Tracy wanted to build sea-going battleships that could project American naval power overseas, though significant elements in the Navy and the United States Congress preferred shallow-draft coastal-defense ships.

The Board concluded that the distance between Europe and North America would hamper European naval attacks, but the power of the British Royal Navy and the possibility of future political developments warranted the construction of a powerful American battle fleet. The Policy Board issued a call for a fleet that would consist of eight first-class battleships, ten slightly smaller second-class battleships, and five third-class ships, along with substantial numbers of lesser craft to support them. The fleet would be tasked with defending the East Coast of the United States, which required an operational range that could cover as far south as the Caribbean Sea, as the Board had determined that any hostile power would need to seize advance bases there to effectively operate against the United States. The three vessels already authorized—Maine, Texas, and what became the armored cruiser New York fit in the third category, so larger and more powerful vessels would have to be built to meet the Board's recommendations.

Congress, dismayed by the Board's conclusions, nevertheless approved funding for three of the first-class battleships in April 1890, which became the Indiana-class battleships. These were low-freeboard vessels intended for local, coastal defense. They were badly overweight when completed, and as a result suffered from serious problems, including belt armor that was fully submerged when the ships were fully loaded, a tendency to ship excessive amounts of water, and poor handling characteristics. Changes in the control of Congress in late 1890 led to delays for the next ship to be authorized until 19 July 1892, when funds were allocated for a "seagoing coastline battleship". The vessel was to be built with a displacement of around 9,000 long tons (9,100 t).

The Policy Board had intended in its original plan that the seagoing ship would trade armor for greater range, but the Bureau of Construction and Repair, responsible for the design of the vessel, decided to reduce the gun armament compared to the Indianas to free up displacement for greater fuel storage. The 13-inch (330 mm) main battery of the Indiana class would be replaced with 12-inch (305 mm) guns, while some of the 8-inch (200 mm) secondary guns would be replaced with faster-firing 4-inch (100 mm) quick-firing guns. Weight would also be saved by the adoption of Harvey armor, which was significantly more effective than compound armor; a thinner belt could thus be used to achieve the same level of protection. The intention to use the new ship for long-range deployments required other changes, in addition to increased coal storage. Since the vessel would necessarily have to operate on the high seas, seaworthiness would have to be improved. This required a greater freeboard, so the ship that was to become Iowa was given a raised forecastle deck that extended from the bow to amidships. The hull was lengthened and displaced more than the Indianas. In addition, the heavy 8-inch gun turrets were moved closer together amidships, which reduced the amount of weight toward the ends of the ship, also contributing to improved sea-keeping. The arrangement also reduced blast interference between the 8-inch and the 12-inch guns.

Iowa had a length at the waterline of 360 feet (110 m) and an overall length of 362 feet 5 inches (110.46 m). Her beam measured 72 feet 3 inches (22.02 m) and she had an average draft of 24 feet (7.3 m). She had a metacentric height of 4.01 feet (1.22 m) and a righting arm of 2.23 feet (0.68 m). She displaced 11,410 long tons (11,590 t) as designed and up to 12,647 long tons (12,850 t) at full load. Steering was controlled with a single rudder; while steaming at 10 knots (19 km/h; 12 mph), she could make a 180-degree turn in 550 yards (500 m), and at a speed of 14 knots (26 km/h; 16 mph), she could make the turn in 390 yards (360 m).