I found this passage in Peter Jelavich's book Berlin Cabaret to be particularly illuminating, especially as regards our own mission statement:
Although the old tradition of popular musical farces had died in the 1870s, the turn of the century saw the emergence of Berlin operetta. This new genre was quite literally an offspring of the variety show. The first Berlin operettas, composed by Paul Lincke (1866-1946), were one-act works that provided part of an evening's entertainment at the Apollotheater, a Vaudeville hall. His first hit was Frau Luna, which premiered on May 1, 1899. The audience was attracted not only by the liveliness of Lincke's music but also by the humor and the plot. The script, written by Heinrich Bolton-Baeckers, called for a group of Berliners to fly to the moon.
This not only allowed a revival of some of the Berlin character-types that had died along with the musical farces, but it also gave the set designers opportunity to create eye-catching decors. Moreover, the work adopted Vaudeville's propensity to feature production numbers with women in tights and outlandish costumes. The success of this combination induced Linke to compose a string of popular works (most notably Berliner Luft, 1904). Other composers and scriptwriters followed suit, as they cranked out a number of spectacular, evening-length "production number operettas".