The Koçgiri rebellion (Kurdish: Serhildana Qoçgiriyê, Turkish: Koçgiri İsyanı) was a Kurdish uprising, that began in the overwhelmingly militant region in present-day eastern Sivas Province in February 1921. The rebellion was initially Alevi, but succeeded in gathering support from nearby Sunni tribes. The tribe leaders had close relations to the Society for the Rise of Kurdistan (SAK). The rebellion was defeated in June 1921.