Hetmans of the Polish–Lithuanian Commonwealth were the highest-ranking military officers, second only to the King, in the Polish–Lithuanian Commonwealth. The first Polish title of Grand Crown Hetman was created in 1505. The title of hetman was given to the leader of Polish Army and until 1581 it was awarded only for a specific campaign or war. Later it became a permanent title, as did all the titles in the Kingdom of Poland and Polish–Lithuanian Commonwealth. It could not be revoked unless treachery had been proven (from 1585). Hetmans were not paid for their services by the Royal Treasury.
From the end of 16th century there were two hetmans in the Grand Duchy of Lithuania and two hetmans in the Crown: a Field Hetman and a Great Hetman (sometimes translated as Grand Hetman). As a result, there were in total four hetman titles: Great Crown Hetman, Field Crown Hetman, Great Lithuanian Hetman and Field Lithuanian Hetman. During joint military operations of the Crown and Grand Duchy of Lithuania armies, the Grand Crown Hetman usually was considered superior to others hetmans and served as commander-in-chief if the war actions ran along the borders of the Grand Duchy and vice versa.
Grand Hetmans were usually in command of the professional and mobilised army and during peace stayed at the capital involving themselves in politics, guarding the interests of the army and planning campaigns.
Polish Field Hetman was subordinates of Grand Hetman and when on the same battlefield commanded the mercenaries and artillery. During peace they usually were deployed on the eastern and southern borders of the Commonwealth, and commanded all local forces against constant skirmishes and small invasions of the Ottoman Empire and its vassals. Field Hetman were also called Frontier Hetman, since they did the same job as commanders of frontier garrisons before the title of hetman was introduced.
Lithuanian Field Hetman initially was called Court Hetman and commanded the guard of the Grand Duke, while Land Hetman commanded militia. Later this difference disappeared and they were renamed Field and Great Hetmans accordingly. Contrary to Polish practice Lithuanian Field Hetman had full control on army under his command and wasn't subordinated to the Great Hetman.