During the reign of Sigismund III Vasa, the Cossack problem was beginning to play its role as Rzeczpospolita's preeminent internal challenge of the 17th century.
Zygmunt III Waza valitsemisajal hakkas kasakaprobleem mängima oma rolli kui 17. sajandi Rzeczpospolita väljapaistev sisemine väljakutse.