The affection that Ernest Hemingway had for Cuba sprang from his love of fishing, and numerous photographs of him brandishing dripping marlin and swordfish testify to his success around the clear waters of the northern cays. He came to know the waters well and, when the United States entered World War II, Hemingway, already having seen action in World War I and the Spanish Civil War, was more than ready to do his bit.
With the full support of the US ambassador to Cuba, Spruille Braden, he began to spy on Nazi sympathizers living in Cuba. He gathered enough information to have his 12m fishing boat Pilar commissioned and equipped by the Chief of Naval Intelligence for Central America as a kind of Q-ship (an armed and disguised merchant ship used as a decoy or to destroy submarines). His search-and-destroy missions for Nazi submarines off the cays continued until 1944 and he was commended by the ambassador, although according to some critics – notably his wife Martha Gellhorn – the whole thing was mainly a ruse for Hemingway to obtain rationed petrol for his fishing trips. Although he never engaged in combat with submarines, Hemingway’s boys’ own fantasies found their way into print in the novel Islands in the Stream.