The effect of the military development efforts associated with the Meiji Restoration were realized in the first Sino-Japanese War (1894–1895). Victory over China ceded Japan the island of Taiwan and established Japan as a regional power. That status was solidified during the Russo-Japanese War (1904–1905) fought over rival imperial ambitions in Manchuria and the Korean Empire. Japan’s victory shocked the West and solidified its status as a major military power – and especially as a naval power with the utter defeat of the Russian fleet at the Battle of Tsushima – a battle that would shape Japan’s own war planning. 

In 1910 Japan formally annexed Korea. A few years later, Japan was technically a member of the World War I allied alliance against Germany. Japan’s military, taking advantage of the great distances and Imperial Germany’s preoccupation with the war in Europe, seized German possessions in the Pacific (Micronesian islands) and German holdings in China, but there was no large-scale mobilization of the economy needed to support their ambitions. Politically, the Japanese Empire seized the opportunity to expand its sphere of influence in China, and to gain recognition as a great power in postwar geopolitics.