The Battle for Miggershausen 1937
This technically quite well-made cartoon from pre-war Nazi Germany is a commercial (or propaganda piece) for Volksempfänger ("people's receiver"), inexpensive radios. First we see agricultural statistics: the far-away village of Miggershausen is quite below standards in milk and egg production. An anthropomorphic radio undertakes the long voyage by express train, steam train, hay carriage to Miggershausen to advertise its services. It is not well received. Then, it collects and leads an army of radios to try again. They flood all the farmhouses and seem to be more convincing that way - at day, they spread agricultural knowledge to bring milk and egg production up to standards; later, they just play music and illustrate how various people enjoy various kinds of music.

Unsichtbare Brücken 1932