Koshamain's Revolt

Koshamain's War (コシャマインの戦い, Koshamain no tatakai) was an armed struggle between the Ainu and Wajin that took place on the Oshima Peninsula of southern Hokkaidō, Japan, in 1457. Escalating out of a dispute over a sword, Koshamain and his followers sacked twelve forts in southern Ezo (), before being overcome by superior forces under Takeda Nobuhiro. The principal record of the conflict is Shinra no Kiroku.

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