Dziga Vertov, director

I was able to find several of this Russian director's films online. There is some information on his life and career at FilmReference.com and here.

Dziga Vertov directed Soviet Toys in 1924:

Cinema Eye is also from 1924. This is a documentary and promotes the joys of life in Soviet Russia:

Man with a Movie Camera (1929) is a Russian experimental documentary:

There is a review here. There are some stills from the film and some study questions and information on Vertov's ideology and technique here and some background information here. I saw this one back in September.

Enthusiasm: Symphony of the Donbass (1931) focuses on the struggles of Soviet miners:

Information on the film here is helpful in viewing the film in context.

Three Songs About Lenin (1934) celebrates Lenin and his role in shaping the USSR:

I'm surprised more of his earlier work is not available online.