Police officers escort refugees onto a train for Holland, Antwerp, 17th June 1939. The refugees have arrived on the German liner MS St. Louis after over a month at sea. The St. Louis' passengers, 937 mainly German-Jewish refugees from Nazi persecution, were denied entry to Cuba, the United States and Canada, before being returned to Europe. (Photo by Gerry Cranham/Fox Photos/Hulton Archive/Getty Images)