Reuter was mayor of Magdeburg from 1931 up to the take-over by the National Socialists; he belonged to the SPD parliamentary group in the Reichstag at the same time. After being arrested several times Ernst Reuter was freed from a concentration camp after help from English friends. He moved to live in the Netherlands, then Great Britain and Turkey. He worked as an adviser for the Turkish government in traffic matters. In 1938 he became a professor for urban development and town planning at the Administration Academy in Ankara.