対華21カ条要求
Japan was now one of the most powerful forces in the Far East, and in 1914, it entered World War I on the side of the Allies, seizing German-occupied Kiaochow and subsequently demanding Chinese acceptance of Japanese political influence and territorial acquisitions (Twenty-One Demands, 1915). Mass protests in Peking in 1919 which sparked widespread Chinese nationalism, coupled with Allied (and particularly U.S.) opinion led to Japan's abandonment of most of the demands and Kiaochow's 1922 return to China. Japan received the German territory from the Treaty of Versailles.