In 1945/46 he had to leave China in an affair about alleged espionage for Japan by German nationals.
In 1964, he was appointed the Chair of the Central Asian seminar at Bonn University.
He not only made a number of invaluable contributions in the academic field, but also edited several popular books on Mongolian history and culture, for example Ein Volk sucht seine Geschichte.
His scientific research work has been acknowledged by elections into various learned societies i.a.
he was elected foreign member of the Mongolian Academy of Sciences which is the highest scientific honour in Mongolia.