Hetman of Ukrainian Cossacks

Hetman of Zaporizhian Cossacks as a military title was not officially recognized internationally until the creation of the Cossack Hetmanate. With the creation of Registered Cossacks units their leaders were officially referred to as hetmans of His Royal Mercy of Zaporozhian Host. Before 1648 and the establishment of Cossack Hetmanate there were numerous regional hetmans across the Dnieper-banks, who usually were starostas or voivodes.

The first widely recognized hetman of Zaporizhia was Dmytro Vyshnevetsky, however later several Polish starostas were added to the Hetman registry such as Lyantskoronsky and Dashkevych who also led their own cossack formations. According to Mykola Hrushevsky they were not really considered as hetman, at least by their contemporaries. Among other such starostas were Karpo Maslo from Cherkasy, Yatsko Bilous (Pereyaslav), Andrushko (Bratslav), and many others. Even Princes Konstanty Ostrogski and were conducting Cossack raids on Tatar uluses (districts).

The commanders of Zaporozhian Host (the Kosh) often considered as hetmans in fact carried a title of Kosh Otaman. As from 1572, hetman was the unofficial title of commanders of the Registered Cossack Army (Ukrainian: Козаки реєстрові, Polish: Kozacy rejestrowi, Russian: Казаки реестровые) of the Polish-Lithuanian Commonwealth. From the 1648 Bohdan Khmelnytsky uprising, Hetman was the title of the head of the Cossack state, the Cossack Hetmanate. Cossack hetmans had very broad powers and acted as supreme military commanders and executive leader (by issuing administrative decrees).

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Wikipedia