From 1937 to 1945 he was imprisoned in the Nazi concentration camps in Dachau and Mauthausen .
Wilhelm Heckmann ( 26 June 1897 in Wellinghofen , Germany -- 10 March 1995 in Wuppertal , Germany ) was a German concert and easy listening musician .
From 1937 to 1945 Wilhelm Heckmann was imprisoned in the Nazi concentration camps in Dachau and Mauthausen .
Wilhelm Heckmann ( 26 June 1897 in Wellinghofen , Germany -- 10 March 1995 in Wuppertal , Germany ) was a German concert and easy listening musician .