The Japanese declared war on the Russians of February 8th. The same day they launched a surprise attack on the Russian Fleet at Port Arthur. The Russians were never able to recover from that point on and lost the war.

Japanese and Russian interest clashed over Manchuria and Korea. The Japanese had gained control over parts of Korea in their war with China. Russia meanwhile wanted to expand its presence in the area, first of all to have an all weather port and second to counter the influence of Great Britain. The Japanese were willing to agree to a compromise which would have recognized their influence in Korea while reconizing Russian influence in Manchuria. Negotiations however did not move forward, the Russians believed that the Japanese would agree to the Russian terms complying with what the Russians believed was their superior military power. The Russians had misjudged the Japanese. Once they had concluded that the Russian negotiations were only designed to delay they decided to attack the Russians. On February 8th they formally declared war on the Russians. Four hours before they delivered their declaration of war the Japanese navy staged a surprise attack on the Russian Fleet in Port Arthur. The attack succeeded in damaging a significant portion of the fleet.

The Japanese then went on to blockading the port. They soon landed troops and surrounded the city. After a long siege and successful Japanese attacks the Russians surrendered the city on January 2, 1905.