Jews were not liked because they;
1) were slaver traders for muslims (in the dark age).
2) had powerful banking system into whole Europe (actually they were not alone - Italians were good rivals) but their cooperation was best
3) were hiring villages from nobles and became supervisors for peasants - then forced peasants to pay horrible taxes
4) cooperated with communists into XX century - many Jews were happily joining and supporting communism system.


In Poland most important were reason 3 and 4. Because of reason 3 many jews were being killed by ukrainian peasants during Chmielnicki uprising.
Into XX century they were not liked, because many Jews joined communist parties and fought against Poland into war with Russia at 1920 year.
Some Jews support Poland into that war, but most of them became neutral or supported Russia.