Wilfried: All the songs I mentioned, except, as you say Maruschka, have perfectly innocent-sounding lyrics. But songs do not only have lyrics and tunes, they have connotations.

I recall once singing Maerkischer Heide - in the basement of the library at U.C. Berkeley, on an evening in or about 1962, believing myself to be alone.

A bald-headed fellow popped out and asked, excitedly, "Sind Sie in der Wehrmacht gewesen?!" (Which was not the case.) And later, as a student in Marburg, I sang it to some (fairly conservative) friends, and was told it was not an acceptable song. So I was curious about that.