Party leaders whom he considered not to have the attributes to be effective party administrators. Consequently, Vahlen was placed on indefinite leave on 1 May 1927 and his newly appointed Deputy, Walther von Corswant, was effectively put in charge. On 21 August, Vahlen was finally dismissed and Corswant officially became Gauleiter. Also in May 1927, Vahlen faced disciplinary actions stemming from an incident a few years earlier when he was Rector at the University of Greifswald. On 11 August 1924, Constitution Day, Vahlen had incited a crowd at the university against the Weimar Republic, which resulted in taking down the flags of the Republic and the Free State of Prussia. The university suspended him for political abuse of his function, and in May 1927 he was dismissed without a pension. Upon his dismissal, Friedrich Schmidt-Ott increased the funding Vahlen had been receiving for his work for the German Navy since 1922. Vahlen worked briefly as an assistant in Johannes Stark's private physics laboratory. In 1930 Vahlen returned to his birthplace and became a lecturer of mathematics at the Technische Hochschule Wien. Once Hitler became Chancellor of Germany on 30 January 1933, Vahlen's career again gained momentum and flourished in Germany as a result of his support for the NSDAP. In that year, he became an ordinarius professor of mathematics at the Humboldt University of Berlin, as successor to Richard Edler von Mises, who emigrated from Germany as a result of the Law for the Restoration of the Professional Civil Service, which was in part directed against professors with Jewish ancestry, which von Mises had. After 1933, Vahlen was a strong advocate of Deutsche Mathematik, a parallel movement to Deutsche Physik, advocated by the Nobel Laureate physicists Philipp Lenard and Johannes Stark; both movements were anti-Semitic. From 1934, he was ordinarius professor at the University of Berlin, a position he held until attaining emeritus status in 1937. In July 1933 Vahlen joined the Sturmabteilung (SA) but on 10 July 1936 he switched to the Schutzstaffel (SS) with the rank of Sturmbannführer and was assigned to the SS Main Office. On 30 January 1938 he was attached to the staff of the Reichsführer-SS. He received successive promotions, the last being to SS-Brigadeführer on 9 November 1943. During the period 1933 to 1937, Vahlen served as third vice president of the Kaiser-Wilhelm Gesellschaft. In January 1934 he became an employee in the University