Thanks for the input---I looked all this up and was surprised to learn about the earlier camps that were situated in Germany proper. Brutal ones.   

I do not know how to refer anyone to the site of this information but will say that it talks of the authors of the song, one of whom was quite involved with Bertold Brecht/Kurt Weill and for a time in later years taught at a Univ. in Calif.

In any case---a moving song and I appreciate the historical revelation to me.

Bill Hahn