Zaporozhian Sich

Free Lands of the Lower Zaporozhian Host
Вольностi Вiйська Запорозького Низового (Ukrainian)
1552–1775
Flag
Cossack with a musket
Historical map of the Ukrainian Cossack Hetmanate (dark green) and the territory of the Zaporozhian Cossacks (purple) between the Russian Empire (khaki), the Crimean Khanate (pink) and the Polish–Lithuanian Commonwealth (yellow)
StatusDe facto independent

De jure vassal of:

CapitalSich (various locations in Zaporozhia)
Common languages
Religion
Eastern Orthodox
DemonymsZaporozhtsi (Zaporozhians), Sichovyky (Sich Cossacks), Rusyny (Ruthenians), Ukraintsi (Ukrainians), Nyzovyky
(members of Lower host)
GovernmentCossack Republic
Kish otaman 
• 1552-1563 (first)
Dmytro Vyshnevetsky
(founder of Khortytsia castle)
• 1765-1775 (last)
Petro Kalnyshevsky
Historical eraEarly modern period
• Established
1552
1775
Population
• 1650
c. 100,000
• 1762
c. 183,700
Preceded by
Succeeded by
Wild Fields
Novorossiya Governorate
Danubian Sich
Today part ofUkraine

The Zaporozhian Sich was a semi-autonomous polity and proto-state of Zaporozhian Cossacks that existed between the 16th to 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 Ottoman Empire, the Tsardom of Russia, and the Russian Empire.

The establishment of Zaporozhian Sich was an important factor in defense of Ukraine and Russia from Crimean-Nogai raids. In c. 1650, its total population consisted of 100,000. In 1657–1687, 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 Zaporozhian Cossack host.