

An ally of Britain, it took control of Germany's Pacific islands during World War I. By 1910, Japan had defeated China and Russia in armed conflicts, annexed Korea and Formosa, and occupied Manchuria. Since the 1860s, it had been swiftly modernizing, transforming itself through industrialization and militarization from a dynastic feudal society to a regional power. Japan was also making its presence known in the Pacific. empire with growing interests in the Pacific. O'ahu was caught up in global geopolitics as the expanding Pearl Harbor Naval Station on the island became the emblem of a fledgling U.S. The next year it sent a force of 1.75 million soldiers to aid the Allies. The nation warmed to its new role, shedding its neutrality in World War I by declaring war on Germany in 1917. By the end of the century, it was a colonial power, having annexed Hawaii, the Philippines, Guam, and Puerto Rico. The traditionally inward-looking but rapidly industrializing United States began to move onto the world stage in the 1890s.
