During the Russo-Japanese War, Port Arthur, the Russian naval
base in China, fell to Japanese naval forces under Admiral
Heihachiro Togo. It was the first in a series of defeats that by
June turned the tide of the imperial conflict irrevocably against
Russia.
In February 1904, following a Russian rejection of a Japanese plan
to divide Manchuria and Korea into spheres of influence, Japan
launched a surprise naval attack on Port Arthur, decimating the
Russian fleet. In the subsequent fighting, Japan won a series of
decisive victories over the Russians, who underestimated the
military potential of its non-Western opponent.
Surrender of the Russian defenders to the Japanese after the Siege of Port Arthur, Russo-Japanese War.