♦Their grievances.♦ There was thus no tie except that of gratitude for their honourable position in war to bind the Cossacks to Poland; and this was soon broken by the outrageous rapacity of the Jewish stewards to whom the nobles entrusted their lands. Complaints were lodged in the Diet by the Cossack chiefs, who claimed to send thither their own representatives; but the nobles, whose love of domination was as strong as their love of liberty, turned a deaf ear; and Wladislas VII., seeing the fatal tendency of this policy, had the hardihood to remind the Cossacks that they still possessed their sabres.[25] ♦Success of their revolt.♦ At length, in 1648, a dastardly outrage by a steward on Bogdan Chmielniçki, one of their chiefs, forced them to follow this hint; and electing the injured man as their hetman, they poured into Poland with the Tartars as their allies. Bogdan was an experienced soldier. He completely defeated Potoçki, the Grand General of Poland, at Korsun (May 26th, 1648); and numbers of disaffected Poles--Arian nobles, Calvinistic burghers, outlawed serfs--at once flocked to his standard. ♦Death of Wladislas VII.♦ Six days before this disaster Wladislas VII. expired at Warsaw; and his death at this moment blighted the hopes of the moderate party. James Sobieski, who had done all he could to save Bogdan from oppression, had died in March (1648) when the king was on the point of naming him the representative of Poland at the congress in Westphalia. ♦Danger of Poland.♦ The nobility in general were bent on revenge. Assembling their forces in haste, they suffered an ignominious defeat at Pilawiecz (September 23rd); and Poland was left exposed to the Cossacks. Madame Sobieska, with her two daughters, and many others of the nobility, took refuge within the walls of Zamosç, and was soon joined by her sons, who had evaded without difficulty the undisciplined besiegers.