Question: This war in which the Japanese cruiser Tokiwa played a large part was fought between which two groups?

Context paragraphs:
James Joseph Magennis: James Joseph Magennis VC (spelling originally McGinnes) (27 October 1919 – 12 February 1986) was a Belfast-born recipient of the Victoria Cross, the highest and most prestigious award for gallantry in the face of the enemy that can be awarded to British and Commonwealth forces.  He was the only native of Northern Ireland to receive the Victoria Cross for Second World War service.  Magennis was part of several operations involving X-Craft midget submarines in attacks on Axis ships.  In July 1945 Magennis was serving on HMS "XE3" during Operation "Struggle".  During an attack on the Japanese cruiser "Takao" in Singapore, Magennis showed extraordinary valour and bravery by leaving the submarine for a second time in order to free some explosive charges that had got caught.  His commanding officer Lieutenant Ian Fraser was also awarded the Victoria Cross for his actions on 31 July 1945 during the operation.

Russo-Japanese War: The Russo–Japanese War (Russian: Русско-японская война , "Russko-yaponskaya voina"; Japanese: 日露戦争 "Nichirosensō"; 1904–05) was fought between the Russian Empire and the Empire of Japan over rival imperial ambitions in Manchuria and Korea.  The major theatres of operations were the Liaodong Peninsula and Mukden in Southern Manchuria and the seas around Korea, Japan and the Yellow Sea.

Manley Laurence Power: Admiral Sir Manley Laurence Power KCB, CBE, DSO & Bar, DL (10 January 1904 – 17 May 1981) was a Royal Navy Admiral who fought in World War II as a Captain and later rose to more senior ranks, including the NATO position Allied Commander-in-Chief, Channel.  He is chiefly remembered for leading the 26th Destroyer Flotilla that sank the Japanese cruiser Haguro in the Malacca Strait during Operation Dukedom.

Japanese cruiser Tokiwa: Tokiwa (常盤 ) was the second and last "Asama"-class armored cruiser built for the Imperial Japanese Navy (IJN) in the late 1890s.  As Japan lacked the industrial capacity to build such warships herself, the ship was built in Britain.  She played minor roles in the Boxer Rebellion of 1900 and World War I, but was very active during the Russo-Japanese War of 1904–05 where she participated in the Battle of Port Arthur, the Battle off Ulsan, and the Battle of Tsushima.  After the war she was sometimes used as a training ship for naval cadets.

Japanese cruiser Ibuki (1943): The Japanese cruiser "Ibuki" (伊吹 ) was a heavy cruiser built for the Imperial Japanese Navy (IJN) during World War II.  The lead ship of her class, she was converted into a light aircraft carrier before completion.  The conversion was delayed and finally stopped in March 1945 in order to concentrate on building small submarines. "Ibuki" was scrapped in the Sasebo Naval Arsenal beginning in 1946.

John Elliott Smart: Lieutenant Commander John Elliott "Jack" Smart (1 March 1916 – 3 February 2008) was an officer in the Royal Navy, who commanded one of the midget submarines that attacked the German cruiser "Lützow" and the Japanese cruiser "Takao" during the Second World War.

Battle of Korsakov: The Battle of Korsakov, a naval engagement of the Russo-Japanese War, was fought on 20 August 1904.  The battle foiled an attempt by the Russian cruiser "Novik" at escaping Port Arthur to join with Russian forces at Vladivostok after the Russian Pacific Squadron was scattered after the Battle of the Yellow Sea.  "Novik" was caught coaling at Korsakov on the island of Sakhalin by the Japanese cruiser "Tsushima" .  After attempting to escape and fighting an engagement with "Tsushima", "Novik"' s crew scuttled their vessel before "Tsushima" and the newly arrived cruiser "Chitose" could finish off the Russian ship.

Battle of Christmas Island: The Battle of Christmas Island was a small engagement which began on 31 March 1942, during World War II.  Because of a mutiny by Indian soldiers against their British officers, Japanese troops were able to occupy Christmas Island without any resistance.  The United States Navy submarine "Seawolf" caused severe damage to the Japanese cruiser "Naka" .

Wayne Moulton: Wayne LaVar Moulton (June 19, 1932 – August 22, 1995) was a motorcycle designer called "the father of the Japanese cruiser."  after introducing specific designs for importers to the lucrative US motorcycle market.  The custom/cruiser market continually occupies one of the biggest slices of the important large displacement US motorcycle market.

Ian Edward Fraser: Ian Edward Fraser, VC, DSC, RD and Bar, JP (18 December 1920 – 1 September 2008) was an English diving pioneer and recipient of the Victoria Cross, the highest and most prestigious award for gallantry in the face of the enemy that can be awarded to British and Commonwealth forces.  Fraser was born in Ealing, London and went to school in High Wycombe.  After initially working on merchant ships and serving in the Royal Naval Reserve, he joined the Royal Navy at the start of the Second World War.  After being awarded the Distinguished Service Cross for actions while serving on submarines, he was placed in command of a midget submarine during an attack in Singapore codenamed Operation Struggle.  For his bravery in successfully navigating the mined waters, and successfully placing mines on a Japanese cruiser, Fraser was awarded the Victoria Cross.

Supporting paragraphs: Japanese cruiser Tokiwa Russo-Japanese War
Answer: the Russian Empire and the Empire of Japan