I expected Congress Dances to be an operetta but it's actually a farcical comedy taking place during the 1814-1815 Congress of Vienna with two very long and elaborately shot musical sequences. Think of it as a sweet Viennese pastry (the story) with two blobs of thick whipped cream (the musical sequences).
On the one hand the story concerns the efforts of the high and mighty to outmaneuver each other in the deal making that went on as Europe was reorganized after the Napoleonic upset. On the other we follow the fairy tale journey of a glove shop sales clerk (Lilian Harvey in her scintillating, elfin prime) into and out of the arms of the visiting Tsar Alexander (Willy Fritsch, excellent in a dual role as the Tsar and his oafish double). Prince Metternich (played smoothly by Conrad Veidt in a very unflattering pouffy looking wig) is busily manipulating the delegates by listening in on their conversations through a network of tubes connecting his bedroom to every corner of the palace, and reading their outgoing and incoming correspondence by placing the sealed envelopes on a backlit glass plate (there were clever spying mechanisms even back then). Much of the footage involves sweeping and elaborate camera movements through dense crowds in streets, palaces, a ballroom and a beer garden. The musical number "Das gibt's nur einmal" transports Harvey in a carriage from her shop through the teeming city streets, into the countryside past dancing peasants and to a grand villa where she runs up the stairs and into a sumptuous bedroom, singing all the way. The song is reprised as a finale of sorts. Earlier we have a beer garden number in which Paul Horbiger strolls among the happy customers singing "Wien und der Wein." The technical complexity of the Harvey number was too much to handle at the time, as evidenced by the way her lip movements are markedly out of synch with the soundtrack. If you watch this and other crowd scenes with no sound they have the flow of late silent cinema, reminiscent of Murnau but also glimmers of Ophuls. Finally, Lil Dagover appears in a few scenes as a French countess sent by Metternich to distract the Tsar from the diplomatic table. But any chance to see the magnificent Dagover should be taken.
The print at the Museum of Modern Art is well worn.