Red Cross messages had been introduced during the First World War, when an urgent need developed for a means that would re-establish the communications that had been severed by the conflict, for example between prisoners of war and their families at home. During the Second World War, as conventional means of communication were increasingly denied to Jews trapped in the Third Reich, Red Cross messages came to play a vital part in what remained of the contacts between those Jews and their family members who had escaped abroad; little systematic attention has, however, as yet been devoted to them.