Norbert Hann von Hannenheim (1898 – 1945, Międzyrzecz) was an Austro-Hungarian-born German and Romanian composer. He is seen as one of the most brilliant later pupils of Arnold Schoenberg.
A member of the Saxon community in Transylvania, Hannenheim was born in the city of Nagyszeben (in German: Hermannstadt, present-day Sibiu). He studied in Graz, Austria, from 1922 to 1923, and subsequently with Paul Graener in Leipzig. Hannenheim was then a pupil in Schoenberg's Master Class in Composition at the Akademie der Künste in Berlin (1929 to 1932). Schoenberg regarded him highly, calling him "one of the most interesting personalities I have ever met".
Hannenheim was a prolific composer and espoused the twelve-note technique even as a student. His works were performed at concerts in the Akademie der Künste (for example, he conducted the premiere of a Symphony in a concert devoted to Schoenberg's pupils on 20 May 1930 — it shared the programme with works by his fellow-students Winfried Zillig and Nikos Skalkottas). He also had works performed at pre-World War II ISCM Festivals (as a Romanian composer, since the ISCM was formally proscribed by the Nazi German musical authorities).
It was long believed that Hannenheim perished in an Allied air raid on Berlin and that all his scores were destroyed, but numerous songs, piano sonatas and string quartets have come to light in recent years, and it now appears that Hannenheim, who had intermittent but acute psychological problems, died in a German psychiatric hospital (probably in Berlin).