You'll fine a larger answer I wrote on the FFL in WWII here, but I'll copy the relevant part here:

As for Germans, well, Germans have always been the heart and soul of the Legion (and remain a key part through today). It is remarked that the Legion is only as strong as its worst German. In the 1930s, there were a fair number of Germans in the Legion. The older ones, who had joined before Hitler's rise, were, for lack of a better description, simply Germans. More recent recruits were to a large degree political exiles and refugees, and quite a few were German Jews. As I said, with the fall of France, this latter group did what they could to be posted far away from Europe - Indochina and Senegal being the prime locations. The former group, is much more interesting. Those who remained with the legion were quite cocky, and openly derisive of France. Some deserted and returned to Germany. Many that remained in North Africa were forced to leave by request of Germany, who shanghaied them into the Heer.