 Jeremi Wiśniowiecki ( Ukrainian : <unk> <unk> - <unk> <unk> ; August 17 , 1612 – August 20 , 1651 ) nicknamed <unk> on the Cossacks or Iron Hand , was a notable member of the aristocracy of the Polish @-@ Lithuanian Commonwealth , Prince of <unk> , <unk> and <unk> in the Crown of the Kingdom of Poland and the father of the future King of Poland , Michael I. 
