Zaporozhian Sich

The Zaporozhian Sich (Ukrainian: Запорозька Січ, Zaporoz'ka Sich; Polish: Sicz Zaporoska; Russian: Запорожская Сечь) was a semi-autonomous polity of Cossacks in the 16th to 18th centuries, centred in the region around today's Kakhovka Reservoir spanning the lower Dnieper river in Ukraine. In different periods the area came under the sovereignty of the Polish-Lithuanian Commonwealth, the Ottoman Empire, the Tsardom of Russia, and the Russian Empire. In 1775, shortly after Russia annexed the territories ceded to it by the Ottoman Empire under the Treaty of Küçük Kaynarca (1774), Saint Petersburg disbanded the Sich and incorporated its territory into the Russian province of Novorossiya.

The Zaporozhian Sich traditionally started from a fortress (sich) built on the Khortytsia island in the middle of the Dnieper River in the present-day Zaporozhia region of Ukraine. The term "Zaporozhian Sich" can also refer metonymically and informally to the whole military-administrative organisation of the Zaporozhian Cossack Host.

The history of Zaporozhian Sich spans six time-periods:

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