Until the 1930s Germany had been the international leader in biochemistry, chemistry, and areas of biology. After WWII, however, molecular biology as a new interdisciplinary scientific enterprise was scarcely represented in Germany for almost 20 years. Three major reasons for the low performance of molecular biology are discussed: first, the forced emigration of Jewish scientists after 1933, which not only led to the expulsion of future distinguished molecular biologists, but also to a strong decline of ''dynamic biochemistry'', a field which (...) contributed greatly to molecular biology. Second, German university structures that strongly impeded interdisciplinary research. Third, the international isolation and self-isolation of German scientists that was a major obstacle to the implementation of new fields of research developed elsewhere. Despite the fact that there was no official boycott against Germany as there had been after WWI and despite the Cold War policy of integrating Germans into the West, as a consequence of National Socialism and WWI for many years only very few German scientists gained access to the international community of molecular biologists. Max Delbruck played an important role in helping the Germans establish modern, mostly molecular, biology because he retained strong connections to Germany. Most importantly, it required a new generation of young scientists who had received part of their training in the US to establish modern molecular biology at German universities and Max Planck Institutes. (shrink)