Lubomirski's Rebellion

Lubomirski's rebellion or Lubomirski's rokosz (Polish: rokosz Lubomirskiego), was a rebellion against Polish King John II Casimir, initiated by the Polish nobleman, Jerzy Sebastian Lubomirski.

In 1665-66, Lubomirski's supporters paralyzed the proceedings of the Sejm. Lubomirski himself, with the support of part of the army and the levée en masse (pospolite ruszenie), defeated royal forces, at the Battle of Matwy (1666). The rebellion ended with the Agreement of Łęgonice, which forced the King to give up his planned reforms and the introduction of vivente-rege royal elections. Lubomirski himself, now a broken man, died soon after.

The mid-17th century was one of the most tragic and difficult periods in the history of the Polish–Lithuanian Commonwealth. The country was devastated by several wars, such as the Khmelnytsky Uprising and the Swedish invasion of Poland. Its international position was weakened, and the chaos was deepened by the ill-functioning system of nobles' democracy (see szlachta privileges, Golden Liberty). In 1652 a Lithuanian deputy to the Sejm, Wladyslaw Sicinski, for the first time in Polish history used the liberum veto, voiding a bill that was about to be introduced. The country was riven by internal conflicts among the magnates, and its central institutions did not function.

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