[dfwgator]

He got along fine with some of the Slavs, even letting some of them into the SS.

Case in point, Poland's neighbors to the south, The Slovaks. Almost identical in every way, Hitler's treatment of the Slovaks was fairly benign, even allowing them a "puppet" State during the war, run by a Catholic Priest. And Slovaks were more than happy to get rid of their Jews.

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German settlers didn't want Slovak land -- too hilly, not fertile enough.

And Germans didn't consider Slovaks to be rivals.

They also knew that they could exploit Czech-Slovak hostility to their advantage.

Poland had over a century of conflict with Germany that made it unlikely that Poles and Germans would ally.

Poland also had a strong orientation towards Britain and France that other countries and peoples in the region didn't share.