Five weeks before the German invasion of Poland in 1939, Rejewski and colleagues presented their achievements to French and British intelligence representatives summoned to Warsaw. Shortly after the outbreak of war, the Polish cryptologists were evacuated to France, where they continued breaking Enigma-enciphered messages. They and their support staff were again compelled to evacuate after the fall of France in June 1940, and they resumed work undercover a few months later in Vichy France.