The Russo-Japanese war took place between 1904 and 1905 over a dispute between Russia and Japan over Russia's occupation of part of China. Russia, seeking a port free from ice all the year round, secured a lease of Port Arthur from China in 1896. Soon the Siberian railway extended into the town; the harbour was deepened; building operations were begun at Dalny, which it was intended to make the great port of Asia; and schemes were broached for elevating Russia into the position of a naval power in the Pacific.
In midsummer 1900 Russia took over the reins of power in the Amur province. She then tried to induce China formally to recognise the military occupation of the province. Both Great Britain and Japan flatly refused to consider the proposal. The following spring Russia promised to withdraw her troops within six months from part of Mukden and south Manchuria, as well as to restore the railway to China; to evacuate Mukden and Kirin altogether within the following six months; and to withdraw from Chinese territory finally within a third period of six months. Russia didn't keep her promise, and in June 1903 Japan proposed an agreement with Russia by which both parties would respect the integrity of China and Korea. Russia refused and in February 1904 Japan withdrew her minister at the Russian capital and three days later attacked the Russian fleets at Chemulpo and Port Arthur and landed troops at Chemulpo. Japanese troops in Korea occupied Seoul and marched north to Pingyang. The Japanese general attacked the opposing Russians on April the 30th on the Yalu, and completely routed them. Russia was defeated, and peace was finally secured by the treaty of Portsmouth (USA) signed on August the 29th 1905. By the treaty the island of Sakhalin was divided between both parties. Russia lost control in Manchuria to Japan, and both parties evacuated China leaving it to China. Research Russo-Japanese War