In the year 1928–29 he visited the University of Göttingen, where topologists such as Pavel Sergeevich Alexandrov and Heinz Hopf were working.

It was here that Seifert submitted his dissertation, Topologie 3-dimensionaler gefaserter Räume (“Topology of 3-dimensional fibred spaces”), on 1 February 1932, and he was awarded with this doctorate of philosophy after his oral examination on March 3.

[2] In 1935, Seifert was summoned to a post at the University of Heidelberg, where he took a position vacated by the dismissal of a Jewish professor.

During World War II he volunteered for a position at a Luftwaffe research center, the Institut für Gasdynamik.

After the war, Seifert was one of the few German professors whom the Allies trusted during the period of denazification.