Zaporozhian Sich

The Zaporozhian Sich was a semi-autonomous polity and proto-state of Zaporozhian Cossacks that existed between the 16th and 18th centuries. For the latter part of that period, it was an autonomous stratocratic state within the Cossack Hetmanate. The lands of Zaporozhian Sich were centred around the Great Meadow region of Ukraine, spanning the lower Dnieper river. In different periods the area came under the sovereignty of the Polish–Lithuanian Commonwealth, the Crimean Khanate (itself a vassal of the Ottoman Empire), the Tsardom of Russia (Muscovy), and the Russian Empire.

The establishment of the Zaporozhian Sich was an important factor in the defense of Ukraine and Russia from Crimean-Nogai raids. Simultaneously, the Cossack raids originating from it caused similar destabilising effects in the region. In c. 1650, its total population consisted of 100,000. In 1657–1687, the Zaporizhian Sich was practically independent, possessing its own administration and armed forces consisting of 12,000–20,000 Cossacks. It was reliant on population growth, mainly consisting of Ukrainian refugees from devastated lands.

In 1775, shortly after Russia annexed the territories ceded to it by the Ottoman Empire under the Treaty of Küçük Kaynarca (1774), Catherine the Great disbanded the Sich. She incorporated its territory into the Russian province of Novorossiya.

The term Zaporozhian Sich can also refer metonymically and informally to the whole military-administrative organisation of the ZaporozhianCossack host.