The difficulties of scientific life in occupied France

Between June 1940 and the end of 1944, a large part of France (and even the whole of France after November 1942) was occupied and adminstrated by the Germans. In the present paper, we present some aspects of the mathematical life in France during this difficult period. We try to illustrate that in institutional life as well as in scientific aspects, one can find a wide range of behaviours adopted by actors who try to adapt to the new situation in the best possible way.