Batalha de Port Arthur (1904), entre o Império Russo e o Japonês no controle de Port Arthur na Manchuria (China).

The Battle of Port Arthur (Japanese: 旅順港閉塞作戦, Ryojunkō Heisoku Sakusen, 8–9 February 1904) was the starting battle of the Russo-Japanese War. It began with a surprise night attack by a squadron of Japanese destroyers on the Russian fleet anchored at Port Arthur, Manchuria, and continued with an engagement of major surface combatants the following morning. The battle ended inconclusively, and further skirmishing off of Port Arthur continued to May 1904. Losing at Port Arthur for the Russians — and especially for Tsar Nicholas II — was not only inconceivable to the world at large but also fraught with dire circumstances for the Imperial Russian regime; the Russian people, from the nobility down to the recently-emancipated serfs, lost confidence in the military; this was a direct causal factor for the Russian Revolution of 1905, and was well-remembered upon yet-more-disastrous defeats in World War I.