Real name: Rudolph Lewysohn

German pianist, composer and and the founder/director of the Nelson Revue, a significant cabaret troupe on the 1930s Berlin nightlife scene.
He was born 8 April 1878 in Berlin, Germany and died 5 February 1960 in Berlin, Germany.

One of his early works included the operetta "Hoheit amüsiert sich" (1911, German lyrics by https://www.discogs.com/artist/654854-Julius-Freund) a.k.a. "The King Has Fun" a.k.a. "Король веселится"