Nikolayevsk Incident

The Nikolayevsk incident (尼港事件, Niko Jiken^?) was a series of events from February through March 1920 during the Allied intervention in the Russian Civil War, culminating in the massacre of several hundred Japanese expatriates and most of the Russian inhabitants of the town of Nikolayevsk-on-Amur in the Russian Far East.

Nikolayevsk-on-Amur was occupied in September 1918 by the Imperial Japanese Army as part of Japan's Siberian Intervention force. In early February 1920, the town had a Japanese civilian community of around 450 people, and a military garrison of 350 men from the Imperial Japanese Army's 14th Infantry Division. In addition to the Japanese presence, the Russian White Army housed a garrison of roughly 300 men. The total civilian population at the time was around 15,000. In January 1920, the town was surrounded by a partisan force nearly 4,000 strong under the command of Yakov Tryapitsyn (), who was loosely allied with the Bolshevik Red Army.

On February 24, 1920, realizing that he was outnumbered and far from reinforcement, the commander of the Japanese garrison allowed Triapitsyn's troops to enter the town under a flag of truce. However, Triapitsyn began to round up and execute White Movement supporters, the only force holding his hand being the small Japanese garrison. On 10 March, he issued an ultimatum to the garrison to voluntarily disarm, to which he was sure the Japanese would not agree. Therefore, the Japanese intervened, launching a surprise attack on 12 March 1920. The attack failed and most of the Japanese troops died, the remaining few only surrendered when the Japanese high command ordered them to do so. Even so, Triapitsyn decided to take revenge, which resulted in the execution of the surviving garrison and the slaughter of all but 122 Japanese civilians – in all around 700 Japanese died shortly thereafter.

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