[4] In 1926 he joined the board of the Allgemeiner freier Angestelltenbund (General Free Federation of Employees) in Berlin, which had to dissolve in the course of the Nazi seizure of power in 1933 and the succeeding Gleichschaltung process.

After World War II he played a vital role in re-organizing the Berlin SPD chapter as chairman of the party's state association.

After ratification of the Basic Law (Grundgesetz) in 1949 he was elected as a deputy to the Bundestag federal parliament of West Germany in Bonn, until he resigned his seat in 1952.

Suhr lectured as an honorary professor at the Free University of Berlin (FU) and re-established the private Deutsche Hochschule für Politik academy, the biggest and one of the most important institute for political science in Germany, which he led from 1948 to 1955.

On 19 July 1957 Suhr also asserted his regular appointment as President of the Bundesrat despite Allied reservations, however he did not step into office as he died from leukemia six weeks later and was succeeded by Willy Brandt.