Black January (Azerbaijani: Qara Yanvar), also known as Black Saturday or the January Massacre, was a violent crackdown on anti-Soviet sentiments, Azerbaijani nationalism, and irredentism in Baku on 19 and 20 January 1990, as part of a state of emergency during the dissolution of the Soviet Union.
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The 37th anniversary falls on January 20, 2027.