From The Art and Popular Culture Encyclopedia
In 1918 he and Hans Richter were introduced to one another by Tristan Tzara. Richter wrote that "The contrast between us, which was that between method and spontaneity, only served to strengthen our mutual attraction (...) for three years we marched side by side, although we fought on separate fronts" (Richter, "Dada: Art and Anti-Art"). In 1920 they began experimenting with film. Eggeling made a film called Diagonale Symphonie, completed in 1924 just before his death.
For more on Eggeling see the book Viking Eggeling 1880-1925 by Louise O’Konor.