Jews started arriving to Poland in XI century so it is really 1,000 years of common history. Main bulk of Jewish people arrived after the Black Death period in Europe as they were accused for causing the plague and often murdered and tortured for it.
Although the plague didn't pass Poland her king at the time (having himself Jewish mistress for years and being opened for people from different backgrounds) let them come and settle in Poland including in the vicinity of the capital (at that time) - Krakow.
Time were good (or excellent) and bad (sometimes, e.g. during Ukrainian revolt of XVII century - awful) for both nations but it was all manageable. Jewish people had their Parliament of Four Regions which meant quite a lot of self governing. Before II WW in Poland lived 3.5 million Jews (that's why it was in occupied Poland that Nazis built their death camps) and every third person living in Warsaw before the war was Jewish.
It was all destroyed during the war and the trauma of it and many things that took place at the time lasted till very recently.
But when I look at the newly opened museum - one dedicated to life not to death, to the history of living, working, worshiping, learning and not to dying I am very happy.
Last but not least I am specially happy that during opening celebration Presidents of both Poland and Israel were present (it was the very first foreign visit of Mr Rivlin - the newly elected President of Israel)!
And here is one of the places on main exhibition - fully reconstructed XVII century synagogue :)
