Being an island has both advantages and drawbacks.
In terms of security, an island nation such as the UK is fortunate to be surrounded by a natural defensive moat – the sea – which presents a major headache for an enemy seeking to invade.
On the other hand, it also means that supplies have to be transported across the sea, and in times of war our supply routes stretched to the furthest reaches of the British Empire, which meant an enemy with an effective navy could block those routes and starve us of vital materials and troops.
Many navies have tried their hand at blockades through the ages, arguably none more successfully than the Royal Navy, which generally had the ships and the men to set up extensive patrols, and the patience to see the blockade through.
But by the 20th Century fleets and tactics had developed to the extent that a belligerent German navy, particularly through the use of U-boats (unterseeboots, or submarines) as well as an effective surface fleet, could pose a considerable threat to Allied shipping. The same, of course, could be said of the British.
In simple terms, an overarching strategy of both the UK and Germany would be to starve the enemy into submission.
During World War 1 the Royal Navy set up a catch-all ‘distant blockade’ of the Central Powers; rather than standing off individual ports, British warships essentially blocked the Channel and North Sea, preventing German shipping (and as the war progressed, neutral shipping that could be assisting the Germans) from getting through.
The Austro-Hungarian empire was also isolated by a blockade in the Adriatic, particularly with the help of the French and Italian navies.
But at the same time, the Central Powers were working hard to cut British sea routes linking her to her empire, disrupting the flow of vital raw materials and manpower that the voracious Great War demanded.
Both sides were relatively successful in their blockades.
Poor harvests and inefficient logistics in Germany intensified the effect of the Allied blockade, leading to increasing malnourishment amongst Germans by the end of 1916, while food shortages in Austria led to widespread civil unrest.
In its turn, the German navy ramped up U-boat activity, which had been a feature since 1914, and by 1917 the UK was starting to feel the pinch as merchant shipping was picked off by highly-experienced submarine commanders.
The answer was the convoy system, a tried and tested method of protecting merchant ships, and which almost immediately reversed the fortunes of the warring alliances, with the Germans finding fewer targets and more supplies safely arriving in British ports.
These duels between convoys and U-boats were somewhat rudimentary, when the events of the World War 2 Battle of the Atlantic are considered – submarines had limited range and countermeasures were basic (spotter balloons looking for periscopes, for example), but the pattern was set for the later conflict, and the development of both vessels and tactics meant the World War 2 scenario was significantly more complex, brutal and potentially decisive.
And although convoys were a feature of Allied plans from 1939, the pattern of the Great War was repeated – German ascendency, a mid-war pivotal point and finally a crushing Allied success.
Mistakes on both sides played their part – the British, for example, failed to anticipate the importance of ocean escorts and had to ‘make do’ for part of the war with ships that were not particularly suited to the role, while the Germans failed to build the U-boat force that could have dealt a potentially decisive blow to the UK early on, instead initially diverting resources to other types of warships.
The German ascendency – epitomised by the so-called ‘Happy Times’ when the U-boats seemed almost untouchable – did indeed threaten to cripple the British war effort as well as British morale, and a crucial element of this period was the so-called ‘mid-Atlantic gap’, a vast tract of ocean where air cover could not be provided for convoys which could be set upon by packs of submarines and powerful surface warships.
But technological advances by the Allies, including long-range aircraft and improved radar and ASDIC (an early form of sonar), swung matters in their favour, and bold tactical developments brought death and destruction on an unsustainable scale to the German navy.
Very soon more U-boats were being sunk than were being built to replace them, and experienced crews were being snuffed out at an alarming rate, while Allied shipments of men and materiel were reaching ports such as Liverpool relatively unhampered, allowing the crucial build-up of forces that would be unleashed onto the shores of Normandy in the summer of 1944.
The factors at play in the Battle of the Atlantic are, or course, far more numerous, complex and subtle than can be described in a few paragraphs, but over the coming days we shall look at some of the important aspects of that theatre, including the vessels involved, tactics, and heroes of the Battle.
But there can be no doubt that the Battle of the Atlantic, which lasted from the first hours of conflict in September 1939 until the last week of May 1945, was as important an element of World War 2 as the Battle of Britain, the Arctic convoys and the Normandy Landings.
Today’s image from the extensive Imperial War Museum collection (© IWM A 5668) shows a Royal Navy escort close to merchantmen on a convoy in October 1941. For more imagery from the Battle of the Atlantic you can search the IWM collection at https://www.iwm.org.uk/collections
This series is by no means a comprehensive review of the Battle of the Atlantic, which was a colossal clash – in terms of casualties alone more than 100,000 men are thought to have died as a direct result to the battle, and more than 4,000 vessels were sunk, while many times more those numbers were involved.
Instead, we have picked out some of the more important or thought-provoking features of the campaign, and would encourage you to read further on individual aspects such as eye-witness accounts from escort ships (both fiction and non-fiction) and the role of Enigma.
