The Bayan class was a group of four armored cruisers built for the Imperial Russian Navy around the beginning of the 20th century.

Bayan was trapped in harbor during the subsequent Siege of Port Arthur, and was sunk by Japanese artillery.

Pallada was the first ship lost by the Russians during World War I when she was sunk by a German submarine in October 1914.

The Bayan class marked a departure from the previous Russian armored cruisers, as they were smaller ships designed to serve as scouts for the fleet rather than as commerce raiders.

[1] The Navy was reasonably pleased with the first ship, Bayan, and decided to order another cruiser after the start of the Russo-Japanese War in February 1904.

Russian shipyards were still unavailable, so the Navy decided to simply order a repeat with minor modifications based on war experience.

This was an attempt to minimize the work load on the Naval Technical Committee (Morskoi tekhnicheskii komitet), but they proved to require more attention than planned and a contract was not signed until 20 April 1905.

They could carry a maximum of 1,100–1,200 long tons (1,118–1,219 t) of coal, which gave the first Bayan a range of 3,900 nautical miles (7,200 km; 4,500 mi) at 10 knots (19 km/h; 12 mph).

[3] The main armament of the Bayan-class ships consisted of two 8-inch (203 mm) 45-caliber guns in single-gun turrets fore and aft of the superstructure.

She suffered minor damage during the Battle of Port Arthur at the beginning of the Russo-Japanese War and participated in the action of 13 April 1904, when Vice Admiral Tōgō Heihachirō successfully lured out a portion of the Pacific Squadron, including Vice Admiral Stepan Makarov's flagship, the battleship Petropavlovsk.

When Makarov spotted the five Japanese battleships, he turned back for Port Arthur, and Petropavlovsk struck a minefield and quickly sank after a mine detonated one of her magazines.

After bombarding Imperial Japanese Army positions on 27 July, Bayan struck a mine and was under repair for the next month or so.

[19] All three of the later ships were assigned to the Baltic Fleet upon completion, although Admiral Makarov was detached to the Mediterranean several times before the start of World War I in 1914.

[22] Admiral Makarov and Bayan fought several inconclusive battles with German ships during the war, including the Battle of Åland Islands in mid–1915,[23] and they also defended Moon Sound during the German invasion of the Estonian islands in late 1917, where Bayan was badly damaged.