I used to work with a Polish guy. He told me that Poland has a very, very sorry history... they have no natural borders as do, for example, the Swiss with the Alps, or Italy with Alps and the ocean. It's basically a large pool table. It's incredibly easy to invade. And of course, they have natural resources that are desirable.
To compound matters, they had a sort of Parliament made up of over 400 barons, each one of which could veto any kind of legislation. So nothing ever got done politically. And of course, with that many people in charge, there were lots of cases of divided loyalties.
The Poles even had to hire their kings and princes from outside their borders! Great deal, eh? "We pay you snot, then assassinate you when we feel like it."
If you look back far enough, the borders have shifted so much that there is not one spot of Polish land which has consistently been Poland for 400 years!
And yet the Poles are some of the most courageous warriors in the world. And their women... some of the most amazingly beautiful women in the world are Polish.
(As a kind of finale, consider this: my co-worker told me that when Soviet Russia moved out of Poland, they billed the Polish government for the cost of "defending Poland with our military!")