Russo-Japanese War: The Japanese battleships Hatsuse and Yashima sank after striking several mines off Port Arthur, China.

The Russo-Japanese War was fought between the Russian Empire and the Empire of Japan over rival imperial ambitions in Manchuria and the Korean Empire. The major land battles of the war were fought on the Liaodong Peninsula and near Mukden in Southern Manchuria, with naval battles taking place in the Yellow Sea and the Sea of Japan.

Hatsuse was a Shikishima-class pre-dreadnought battleship built for the Imperial Japanese Navy (IJN) in the late 1890s. As Japan lacked the industrial capacity to build such warships, the ship was designed and built in the United Kingdom. She participated in the early stages of the Russo-Japanese War of 1904–1905, including the Battle of Port Arthur on the second day of the war, as the flagship of the 1st Division. Hatsuse was involved in the subsequent naval operations until she sank in a Russian minefield off Port Arthur on 15 May 1904 after the ship struck two mines. The ship struck one mine which caused significant damage. Less than two hours later, the ship struck a second mine which detonated one of her magazines and Hatsuse sank almost immediately afterwards with the loss of over half her crew.

Yashima was a Fuji-class pre-dreadnought battleship built for the Imperial Japanese Navy (IJN) in the 1890s. As Japan lacked the industrial capacity to construct such vessels, the ship was designed and built in the United Kingdom. She participated in the early stages of the Russo-Japanese War of 1904–1905, including the Battle of Port Arthur on the second day of the war. Yashima was involved in subsequent operations until she struck two mines off Port Arthur in May 1904. The ship did not sink immediately, but capsized while under tow later that day. The Japanese were able to keep her loss a secret from the Russians for over a year.