The rise of militarism after the May 15 Incident and the February 26 Incident, the end of party politics during the latter half of the 1930s, the intensification of the Second Sino-Japanese War which broke out in 1937, and the tension of global international relations, had resulted in the National Mobilization Law and the abandonment of the Tokyo Olympics in 1938. World War II began in Europe in 1939.