After having been editor of the Deutsche Dichterhalle in Leipzig, in 1873 he founded the Neue Monatshefte für Dichtkunst und Kritik.

His critiques in the feuilletons of the newspapers sparkle with humour, at the same time doing justice to authors and actors.

Together with Gustav Kadelburg he wrote several comedies like the famous The White Horse Inn.

As a researcher in literature, he became famous for his edition of the works of Christian Dietrich Grabbe.

Blumenthal is also known for his humorous aphorisms, for example: Das ist ein hässliches Gebrechen, Wenn Menschen wie die Bücher sprechen.