These ships had a complex and prolonged design process which was hampered by constantly changing requirements and the Great Purge in 1937.

They were laid down in 1939, with an estimated completion date in 1944, but Stalin's naval construction program was more ambitious than the shipbuilding and armaments industries could handle.

This is why the Soviets bought twelve surplus 38-centimeter (15.0 in) SK C/34 guns, and their twin turrets, similar to those used in the Bismarck-class battleships, from Germany in 1940.

The ships were partially redesigned to accommodate them, after construction had already begun, but no turrets were actually delivered before Germany invaded the following year.

The Project 25 design was accepted in mid-1937 after major revisions in the armor scheme and the machinery layout and four were ordered with construction to begin in late 1937 and early 1938.

However, this decision occurred right before the Great Purge began to hit the Navy in August 1937 and two of the ship's designers were arrested and executed within a year.

[1] However the Soviet Navy still felt a need for a fast ship that could deal with enemy cruisers and the original concept was revived as Project 69.

A revised design was finished by October which was wargamed against the Japanese Kongō-class battlecruisers, the French Dunkerque-class battleships as well as the Scharnhorst class.

The Navy's Shipbuilding Administration thought that the original secondary armament of 130-millimeter (5.1 in) guns was too small and that the armor on the turrets, conning tower and the forward transverse bulkhead was too thin.

A revised, 35,000-ton design with 152-millimeter (6.0 in) guns and extra armor was submitted to the State Defense Council in January 1939.

The Shipbuilding Commissariat reported on 17 April that it was possible so the agreement was finalized in November 1940 with the deliveries scheduled from October 1941 to 28 March 1943.

[5] The new turrets required more electrical power which meant that the output of the turbo generators had to be increased to 1,300 kilowatts.

The detailed design was supposed to be completed by 15 October 1941, but it was rendered pointless when the Germans invaded the Soviet Union in June.

[7] The hull form was very full with a block coefficient of 0.61 which compared badly to the 0.54 of the Dunkerque, the 0.52 of the German O-class battlecruiser or the 0.5266 of the American Alaska-class cruiser.

[10] The main armament was initially going to consist of three electrically powered triple-gun turrets, each with three 54-caliber 305 mm B-50 guns.

They had a fixed loading angle of 6° and their rate of fire varied with the time required to relay the gun.

The gun fired 470-kilogram (1,040 lb) armor-piercing projectiles at a muzzle velocity of 900 m/s (3,000 ft/s); this provided a maximum range of 47,580 meters (52,030 yd).

[12] The secondary armament consisted of eight 57-caliber B-38 152 mm guns mounted in four twin-gun turrets concentrated at the forward end of the superstructure.

[15] Light AA defense was handled by six quadruple, water-cooled mounts fitted with 37 mm (1.5 in) 70-K guns.

These had two 8-meter (26 ft 3 in) stereoscopic rangefinders, one to track the target and the other to measure the range to the ship's own shell splashes.

The main belt was 230 millimeters (9.1 in) thick, with a taper to the lower edge, and inclined outwards six degrees.

The underwater protection was an American-style design with a bulge and four longitudinal bulkheads intended to withstand a 500-kilogram (1,102 lb) warhead of TNT.

[9] The Soviet shipbuilding and related industries proved to be incapable of supporting the construction of the four Sovetsky Soyuz-class battleships as well as the two Kronshtadt-class battlecruisers at the same time.

Shipbuilding steel proved to be in short supply in 1939–1940 and a number of batches were rejected because they did not meet specifications.

An attempt to import 14,000 long tons (14,225 t) of steel and armor plate from the United States in 1939 failed, probably as a result of the Soviet invasion of Poland on 17 September 1939.

[20] The ships were originally intended to be laid down 1 September 1939, but they were delayed until November to allow improvements to the shipyards to be completed.

Some of her material was used during the siege of Leningrad to repair other ships and in defensive works, but she could have been finished after the end of the war.

Proposals were made to complete her as an aircraft carrier and as a base ship for a whaling flotilla, but both ideas were rejected and she was ordered scrapped on 24 March 1947.

Before the Germans evacuated the city they damaged her building slip and hull with explosives and made her a constructive total loss.