Krzysztof Kosiński, also known as Kryshtof Kosynsky (, Kryshtof Kosynsky; ; 1545–1593), was a Cossack noble from the Podlachia region. He was a colonel of the Registered Cossacks and self-proclaimed hetman. He led two consecutive rebellions against the local Ruthenian nobility, known as the Kosiński uprising.

Life

The Kosiński uprising (1591–1593) is a name applied to two rebellions in the eastern parts of the Polish–Lithuanian Commonwealth (modern-day Ukraine) organised by Krzysztof Kosiński against the local Ruthenian nobility and magnates. His forces were first defeated by Duke Janusz Ostrogski in the Battle of Piątek on 2 February 1593. Kosiński promised to subject his forces to the Polish Monarchy; however, he soon escaped to Zaporizhzhia, where he began organizing a new army. In 1593 he set out for Cherkasy but was soon killed.