Hetmans of Ukraine
At the end of the sixteenth century, the commanders of the Zaporizhian Cossacks were called Koshovyi Otaman or Hetmans ( for example: Christof Kosynsky - first zaporizhian hetman ). In 1572, the hetman was a commander of the Registered Cossack Army (Ukrainian: Реєстрове козацьке військо) of the Rzecz Pospolita too. From 1648, the start of Bohdan Khmelnytsky's uprising, a hetman was the head of the whole Ukrainian State - Hetmanshchyna. Although they were elected, Ukrainian Hetmans had very broad powers and acted as heads of the Cossack state, their supreme military commanders, and top legislators (by issuing administrative decrees).
After the split of Ukraine along the Dnieper River by the 1667 Polish-Russian Treaty of Andrusovo, Ukrainian Cossacks (and Cossack Hetmans) became known as Left-bank Cossacks (of the Cossack Hetmanate) and Right-bank Cossacks.
In the Russian Empire, the office of Cossack Hetman was abolished by Catherine II of Russia in 1764. The last Hetman of the Zaporozhian Army (the formal title of the Hetman of Ukraine) was Kyrylo Rozumovsky who reigned from 1751 until 1764.
The title was revived in Ukraine during the revolution of 1917 to 1920. In early 1918, a conservative German-supported coup overthrew the radical socialist Ukrainian Central Rada and its Ukrainian People's Republic, establishing a "Hetmanate" or monarchy headed by Pavlo Skoropadsky who claimed the title "Hetman of Ukraine". This regime lasted until late 1918 when it was overthrown by a new "Directory" of the re-established Ukrainian People's Republic.
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