The Royal Navy
Britain, as an island nation, has always been highly dependent on sea-going trade. During WWII this was even more the case, and Britain needed to import over 1 million tons of supplies every week to be able to feed and equip its population and war machine. In order to meet the demands, the nation had to rely on resources drawn from its Empire and other trading partners around the world.
It was the Royal Navy's responsibility to project Britain's military, political and economic power. It was also responsible for protecting the sea lanes and the nations lifelines.
At the start of the war, Britain possessed the world's largest fleet. Royal Navy fought well in the Second World War, better than in the First, but the price was high. Some 1,525 vessels of all sizes were lost, including 224 large warships. Over 50,000 British naval personnel lost their lives, a total more than all the men and women currently serving in today's Royal Navy and Royal Marines, and 20,000 more than in the First World War.
By 1945 the Royal Navy had grown to almost 900 major warships and a force of 866,000 men and women.
At the start of the Atlantic theatre of the war the Royal Navy lacked sufficient convoy escorts and air cover was almost non-existent. Large numbers of 1,000-ton coastal escorts, 62 metres long and based on a whale catcher design were built.
Despite their small size these Corvettes were used as ocean escorts but were very uncomfortable in heavy weather. They carried a 102mm gun and up to seventy-two depth charges. The Corvettes played a key role in the Battle of the Atlantic. In 1942, ocean-going escorts called Frigates, 1,400-ton ships just over 90 metres long and capable of 20 knots, were introduced.
In 1941 more ships were placed in convoys, now escorted all the way across the Atlantic. Advances in radio intelligence and code breaking allowed these convoys to be routed around the U-boats. The German effort was largely contained until the USA entered the war and delays in introducing coastal convoys off the American coast and in the Caribbean boosted losses once more. Convoys were introduced to solve this problem and, by late 1942, the U-boats returned in larger numbers to the mid-Atlantic. They were searching for weaknesses in convoy defences that could be exploited by 'wolf packs' of U-boats.
The Battle of the Atlantic, as it became known, now rose to a peak. Britain had lost the ability to decrypt U-boat signals but, in any case, there were too many U-boats to avoid. The Germans concentrated their wolf packs where air cover was not available, the 'black hole' in mid-Atlantic.
A combination of factors finally tilted the balance against the Germans. The British again broke the German codes so they could concentrate escorts around threatened convoys. Most importantly the RAF agreed to the Admiralty's demands for very long range Liberator maritime patrol aircraft to support the escorts in the 'black hole'. Small escort carriers were also deployed to protect convoys.
The German offensive was failing and on 23 May 1943 the Germans withdrew their U-boats from the Atlantic campaign. This withdrawal was only temporary but later German efforts were broken by the now formidable escort forces. The Battle of the Atlantic had been won. By the end of the war the losses suffered by both sides were appalling. The Allies lost 30,000 seamen and 2,500 merchant ships were sunk.