Cabaret artist. composer and lyricist of Jewish descent born in Magdeburg. After the Nazis took power in 1933 he had to leave Germany and via Switzerland and Austria he emigrated to The Netherlands. In 1942 Rosen was incarcerated in the Dutch Westerbork transit camp and in 1944 deported to Theresienstadt. Then he was sent to Auschwitz, where he died in the gas chamber.