When the Nazis came to power, most contemporary art was banned and removed from museums and private collections (and sold abroad for the financial benefit of the Reich). What the Nazis really wanted to see they put into their House of German Art.
BTW, the building survived World War II and still serves as an art museum. However, now they have actual art there (and good one, too). In any case, if you ever happen to be in Munich look around a little bit. Munich is one of the feew places where you can still see Nazi architecture (but don't ask the locals - they'll deny it).
