Over 30,000 seamen from the British merchant navy were lost between 1939 and 1945 and thousands more from the American and other Allied merchant navies. One in 26 US mariners serving aboard merchant vessels in World War II died in the frontline of duty, suffering a greater percentage of war-related deaths than all other US services. Theirs was a constantly fought battle with no respite. Even during the so-called ‘Phoney War’ between September 1939 and May 1940, 177 British merchant ships were lost, and for almost six years afterwards barely a day went by without the loss of merchant ships and their civilian crews. In total, approximately 12 million tons of merchant shipping was lost during the Battle of the Atlantic. Great secrecy surrounded the deployment of convoys and the crews and their families were constantly reminded of the importance of this. At the time the high casualty rate was kept secret to attract and keep mariners at sea. This possibly contributed to the lack of public recognition merchant mariners received post-war for their valiant service. Nonetheless, the dangers they faced were acknowledged by the Allied servicemen drafted to protect them, in the words of one: Those of us who have escorted convoys in either of the great wars can never forget the days and especially the nights spent in company with those slow-moving squadrons of iron tramps, the wisps of smoke from their funnels, the phosphorescent wakes, the metallic clang of iron doors at the end of the night watches which told us that the Merchant Service firemen were coming up after four hours in the heated engine rooms, or boiler rooms, where they had run the gauntlet of torpedoes or mines for perhaps half the years of the war. I remember so often thinking that those in the engine rooms, if they were torpedoed, would probably be drowned before they reached the engine room steps...’ This chart shows the principal causes of damage to Allied merchant shipping. Contrary to the pre-war belief of both German and British naval leaders, the surface ship played only a small role in inflicting damage against Allied merchant ships; the submarine was by far the greatest menace.