Mostly because I was interested in Prussian history and Poland is a large part of historical Prussia. That particular piece of geography has always been a battle zone it seems. Prussia of course was a Germanic state and in the 19th century was about as close to a world super power as it got at that time, it was the most powerful of the Germanic states, probably even more powerful than the Austro-Hungarian Empire (Hapsburgh's).
I started reading up about it and just found it fascinating how a country that powerful completely ceased to exist.