May 15 Incident

The May 15 Incident (五・一五事件, Goichigo Jiken^?) was an attempted coup d'état in Japan, on May 15, 1932, launched by reactionary elements of the Imperial Japanese Navy, aided by cadets in the Imperial Japanese Army and civilian remnants of the ultra nationalist League of Blood. Prime Minister Inukai Tsuyoshi was assassinated by 11 young naval officers. The following trial and popular support of the Japanese population led to extremely light sentences for the assassins, strengthening the rising power of Japanese militarism and weakening democracy and the rule of law in Japan.

As a result of the ratification of the London Naval Treaty limiting the size of the Imperial Japanese Navy, a movement grew within the junior officer corps to overthrow the government, and to replace it with military rule. This movement had parallels in the Sakurakai secret society organized within the Imperial Japanese Army. The naval officers established contacts with the ultranationalist Inoue Nissho and his "League of Blood", and agreed with his philosophy that to bring about a "Shōwa Restoration", it would be necessary to assassinate leading political and business figures.

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