 After the death of Batory in 1586 , Zamoyski helped Sigismund III Vasa gain the Polish throne , fighting in the brief civil war against the forces supporting Habsburg archduke Maximilian III of Austria . The camp supporting Sigismund was rallied around Zamoyski , whereas Maximilian was supported by the Zborowski family . Zamoyski defended Kraków and defeated Maximilian 's forces in the Battle of Byczyna in 1588 . In that battle , which Sławomir Leśniewski describes as " one of the most important in Polish history , and the most important in Zamoyski 's military career " , Maximilian was taken prisoner and in the resulting Treaty of Bytom and Będzin of 1589 had to give up all pretenses to the Polish crown . Later that year Zamoyski proposed a reform of the royal elections , which failed to pass the Sejm . 
