Following the Russian rejection of a Japanese program to divide Manchuria and Korea into spheres of influence, Japan launches a surprise naval attack against Port Arthur, a Russian naval base in China. The Russian fleet was decimated.
During the next Russo-Japanese War, Japan won a number of decisive victories a lot more than the Russians, who underestimated the military potential of its non-Western opponent. In January 1905, the strategic naval base of Port Arthur fell to Japanese naval forces beneath Admiral Heihachiro Togo in March, Russian troops were defeated at Shenyang, China, by Japanese Field Marshal Iwao Oyama and in May, the Russian Baltic fleet beneath Admiral Zinovi Rozhdestvenski was destroyed by Togo close to the Tsushima Islands.
These 3 major defeats convinced Russia that additional resistance against Japan’s imperial styles for East Asia was hopeless, and in August 1905 U.S. President Theodore Roosevelt mediated a peace treaty at Portsmouth, New Hampshire. (He was later awarded the Nobel Peace Prize because of this achievement.) Japan emerged from the conflict because the very first present day non-Western world energy and set its sights on greater imperial expansion. However, for Russia, its military’s disastrous efficiency in the war was 1 of the immediate factors behind the Russian Revolution of 1905.