At the start of World War II in 1939, the Royal Navy was the largest in the world, but it suffered huge losses in the early stages, including the battle ships HMS Courageous, HMS Glorious and HMS Hood in the European Theatre, and HMS Repulse and HMS Prince of Wales off Singapore. WW2 records state that of the 1418 men on the Hood, only 3 survived, and over 3000 people were lost when the converted troopship Lancastria was sunk in June 1940, creating the greatest maritime disaster in Britain's history.
The Navy's role during WW2 was to provide cover during evacuations and operations; guard the sea lanes enabling British armed forces to fight in remote parts of the world such as North Africa, the Mediterranean and the Far East, and escort convoys across the Atlantic and Arctic Oceans and protect them from air, surface and submarine attack.
Successes against enemy naval ships included the sinking of the Bismarck, which effectively ended Germany's surface ship capabilities, and the German battleship Scharnhorst. The Royal Navy provided critical cover during British evacuations from Dunkirk, and launched the first all-aircraft naval attack in military history at the Battle of Taranto.
Although there are large numbers of naval records relating to the Second World War, it is difficult to isolate specific Royal Navy records for WWII losses. This is partly due to the integration of the three armed services, and to the addition of the British merchant fleet and its resources, as well as civil government and allied forces.
A preliminary British military report on war casualties in June 1946 listed the numbers of war dead by Navy, Army, Air Force, Women's Auxiliary Territorial Service, Merchant Navy, British Home Guard and Civilians. Records indicate 50,758 Royal Navy deaths as well as 30,248 Merchant Navy deaths, and include figures from the losses of Newfoundland and Southern Rhodesia.