Background: the Anglo-Japanese Alliance
In 1902, Japan and Great Britain concluded an agreement for a formal alliance. The alliance included a number of important benefits for Japan. At the turn of the twentieth century, Japan was trying to modernize its navy, and Great Britain (then the world’s premier naval power) agreed to provide training for Japanese naval officers.
Even more important were mutual defense clauses of the alliance. Japan and Great Britain agreed to come to each other’s aid in the event that either country was at war with two or more nations. In wars involving one against one, both countries simply agreed to remain neutral. This aspect of the alliance would be Japan’s insurance policy in its 1904-1905 war with Russia.
Tensions in Korea
By the early 1900s, tensions between Czarist Russia and Japan were building. Both countries wanted to dominate Korea and the Chinese region of Manchuria; and Russia was already placing troops in both areas.
The Japanese were still simmering from an earlier humiliation at the hands of the Western powers. In 1895, Japan had won a brief war with China. The original peace treaty gave Japan the rights to the Chinese Liaodong peninsula. But Japan was not to enjoy this part of its victory. Russia colluded with France and Germany to force the Japanese to give up their claims to Liaodong. Then three years later, the Czar pressured the Chinese government to allow a Russian base on the Liaodong peninsula, at the strategically important seaport of Port Arthur. Port Arthur allowed direct sea access to both Japan and Korea.
The Japanese opened negotiations to reduce the Russian military presence that was growing at their back doorstep, but these talks were ultimately fruitless. The Japanese government determined that military action was its only option.
Japan’s alliance with Britain assured that the war with Russia would be limited. If not for the Anglo-Japanese alliance, taking on Russia would have meant a war with France as well. (France and Czarist Russia were close allies.) But the Japanese figured (correctly, as it turned out) that France would not risk war with Great Britain.