▁When ▁Henry ▁IV ▁Pro bus ▁took ▁control ▁over ▁Krak ów ▁after ▁the ▁death ▁of ▁Les zek ▁II ▁the ▁Black ▁in ▁ 1 2 8 8 , ▁he ▁could ▁count ▁on ▁the ▁support ▁of ▁the ▁Duke ▁of ▁Ś c ina wa . ▁ ▁Death ▁Pr zem ko ▁died ▁during ▁the ▁Battle ▁of ▁S iew ierz ▁between ▁Henry ▁IV ▁Pro bus ▁and ▁the ▁coal ition ▁formed ▁by ▁Duke ▁B oles ław ▁II ▁of ▁P ł ock ▁and ▁Duke ▁W ład ys ław ▁I ▁the ▁El bow - high ▁of ▁K uy avia . ▁According ▁to ▁the ▁Chron icle ▁of ▁Jan ▁D ług osz , ▁the ▁exact ▁date ▁of ▁the ▁battle ▁was ▁ 2 6 ▁February ▁ 1 2 9 0 ; ▁however , ▁ 2 6 ▁February ▁ 1 2 8 9 ▁seems ▁a ▁more ▁likely ▁date , ▁and ▁is ▁given ▁by ▁other ▁sources . ▁ ▁His ▁death ▁had ▁a ▁very ▁v ivid ▁description , ▁thanks ▁to ▁the ▁Nag rob ków ▁ksi ąż ą t ▁ś lą skich ▁and ▁the ▁K ron iki ▁ksi ąż ą t ▁pol skich . ▁According ▁to ▁these ▁sources , ▁he ▁was ▁taken ▁prisoner ▁among ▁other ▁S iles ian ▁D uk es , ▁but ▁during ▁the ▁subsequent ▁confusion ▁after ▁the ▁defeat , ▁he ▁was ▁murder ed ▁in ▁the ▁battle field . ▁ ▁The ▁key ▁to ▁the ▁interpretation ▁of ▁both ▁sources , ▁could ▁be ▁found ▁in ▁the ▁Duke ' s ▁grave ▁in ▁the ▁ ▁C is tern ian ▁monaster y ▁of ▁Lub i ąż , ▁who ▁was ▁possibly ▁the ▁main ▁cause