During the early phases of World War II, the Royal Navy provided critical cover during British evacuations from Norway (where an aircraft carrier and 6 destroyers were lost but 338,000 men were evacuated), from Dunkirk (where 7,000 RN men were killed) and at the Battle of Crete.
Under de tidlige faser af krigen forestod Royal Navy det vigtige luftforsvar af evakueringen af de britiske styrker fra Norge (hvor man tabte et hangarskib og seks destroyere, men stadig evakuerede 338.000 soldater), Dunkirk (hvor 7.000 sømænd mistede livet) samt Kreta.