Operation Sealion - The German Invasion of Britain Pillboxes - Images of An Unfought Battle Operation Sealion, the German Invasion of Britain 1940. "The German Paratroops jumped at dawn, as they had done in Holland, in Belgium, in Norway. But this time there were more of them. Nearly 8000 Fallschirmjager of the 7th Fliegerdivision, carried by a stream of 600 Junkers 52 transports. The time was 6 o'clock on the morning of September 22nd 1940, just a few minutes after the official sunrise on a grey cloudy, windless day. Below the long lines of aircraft the unwontedly calm sea was dark with the countless barges and motorboats of the invasion fleet. By breakfastime close on 90,000 troops were successfully ashore on the beaches between Folkestone and Seaford. Operation Sealion had begun." Excerpt from Sealion by Richard Cox. By June 1940, less than a year after the start of the war, the German Army had overrun France, Poland, Holland, Belgium, Denmark and Norway.

The beaten British Army had withdrawn from Dunkirk without its heavy weapons and equipment. Britain now stood alone against a German dominated Europe, with only 25 miles of the English Channel separating it from the victorious German armies. Britain was very weak, but still had a strong airforce and navy. Germany expected Britain to surrender, but although isolated it did not surrender. On June 4th the new Prime Minister Winston Churchill made his now famous "... we shall fight them on the beaches..." speech. Germany had two options, to besiege to Britain or to invade it. On 16th July 1940 Hitler issued his Directive 16 "...I have decided to begin to prepare for, and if necessary to carry out an invasion of England.." The operation was given the codeword Sealion. The German Navy was reluctant to attempt an invasion. It was inexperienced in amphibious warfare, its navy was weak and it knew full well how powerful the Royal Navy was. However, the Army was keener and plans were hastily drawn up. It was possible that Hitler was bluffing, but realised that full scale preparations were needed to convince the British to either come to terms or surrender. The German Invasion Plans.

The Army wanted to land on a 200 mile wide front stretching from Lyme Regis in the west to Ramsgate in the east, however the Navy was constantly worried about the threat from the Royal Navy insisted on a narrower landing. A compromise was arrived at where the landings would be from Brighton in the west to Folkestone in the east. The first wave of about 60,000 men was to secure the beaches while the second wave comprised of the tank divisions that were to break out of the beachheads and capture the secondary objectives. The landings were to be assisted by airborne troops landing on the Downs above Brighton and north-west of Folkestone to help with the capture of crossings over the Royal Military Canal. The British Defences. In Britain defences were hastily erected. On 14th May 1940 the Local Defence Volunteers were formed. It was made up of men too old, or too infirm to join the regular army. The LDV later became known as the Home Guard after Churchill used the phrase in a radio broadcast. General Sir Edmund Ironside was put in charge of Britain's defence.

With the lack of equipment he decided to build a static system of defences which could delay the Germans long enough for more mobile forces to counter attack. The defences were made up of concrete pillboxes , anti-tank obstacles, trenches and minefields which took advantage of natural and man made features. The main line of these defences was known as the GHQ Stop Line. In July 1940 General Ironside was replaced as commander of the Home Forces by General Alan Brooke. General Brooke changed the defence strategy away from static defence lines to mobile formations, although defence lines continued to be built. The Germans Attack. For the invasion to succeed the Germans had to defeat the Royal Air Force. The air offensive began on 12th August. At first the Germans concentrated on the radar stations and airfields of the RAF. Unknown to the Germans these tactics soon had the RAF almost on its knees. However, the Germans changed tactics and started bombing London and the aircraft factories, thereby allowing the RAF to regroup. Legend has it that the German decision to bomb London was caused by RAF raids on Berlin, which in turn was caused by a German bomber crew losing their way and accidentally releasing their load over London. Codeword Cromwell - Invasion Imminent.

In the first week of September reconnaissance of the Channel ports -Ostend, Le Havre, Flushing, Ostend, Dunkirk and Calais- had shown a substantial build-up of barges. At Ostend alone 280 had arrived during the previous week. Substantial numbers of motor-boats and larger vessels had also moved down the coast to the same area. Considerable numbers of bombers had just moved to airfields in the Low Countries and dive-bombers appeared to be assembling near the Straits of Dover. The moon and tide favoured a landing between September 8th and 10th. Everything pointed to an invasion. At 5.20 p.m on 7th September the Chiefs of Staff met. At 8.07 p.m. they decided to bring Home Forces to a state of "immediate readiness" and issued the word ï¿½Cromwellï¿½ meaning invasion imminent. 8pm on a Saturday night was not a good time to raise an alarm. Most duty officers at military commands were junior officers, who in the main had not been briefed fully on procedures. Many thought the signal meant an invasion had already begun.

All over the country coastal artillery sites were manned, thousands of units put on steel helmets and waited for first sight of the enemy. Home Guard units were mobilised and manned their pillboxes and their improvised defences. The Beetle invasion warning network, just completed days earlier on August 26th, crackled into life and Operation Banquet was initiated whereby all flyable training aircraft that werenï¿½t fighters were converted into bombers. Police rounded up trainee pilots, some barely able to fly, from pubs, dance halls and cinemas and as they reported back to their airfields they were shocked to see bombs being loaded onto their flimsy training aircraft. More than half of Bomber Command's medium bombers stood by to support Home Forces. Some Home Guard Captains sounded church bells, which they were only supposed to do on their own initiative if they actually saw more than 25 of the enemy, and other units, both Home Guard and the regular Army, thought the bells were confirmation of enemy troops in the area. Several East Anglian bridges were blown up by the Royal Engineers and there were more serious consequences when three Guards officers were killed in Lincolnshire when their vehicle went over a newly laid mine as they rushed back to their unit.

As daylight dawned on the 8th it was clear that Sealion had not been launched and gradually senior officers managed to restore sanity to the situation Indecision and Postponement. With the failure of the German Air Force to defeat the Royal Air Force the German High Command became increasingly nervous about the chances of a successful invasion. Initally it was intended to invade in August but on 3rd September the High Command postponed Sealion to the 21st and then the 27th which would be the last time that year the tides would be suitable. On 15th September the German Air Force launched a major attack to destroy the RAF. The Germans lost twice as many planes as the RAF. This signalled the end for Sealion. Hitler had it postponed indefinitely, while his attention was drawn towards the Soviet Union. Conclusions There a two schools of thought on how successful a German Invasion would have been had the RAF been defeated. The first is that a German invasion, even with air superiority would have probably failed. In 1974 a wargame was played at the Royal Military Academy Sandhurst.

The wargame involved a number of senior military men from both sides including Adolf Galland the famous Luftwaffe fighter ace and Air Chief Marshal Sir Christopher Foxley-Norris. It presumed that the Luftwaffe has not yet won air supremacy and utilised previously unpublished Admiralty weather records for September 1940. Even without air supremacy the Germans were able to establish a beachhead in England using a minefield screen in the English Channel to protect the initial landings from the Royal Navy. However, after a few days, the Royal Navy was able to cut off supplies from the German beachhead, isolating them and forcing their surrender. The second is that , with the Luftwaffe dominating british skies, they would have been able to target oil refineries, industry and ports relatively unimpeded. Combined with a blockade by U-Boats Britain would have been starved either into surrender or a negotiated peace with Nazi Germany. What Might Have been... "Later that afternoon with the Germans already in Trafalgar Square and advancing down Whitehall to take their position in the rear, the enemy unit advancing across St. James 'Park made their final charge. Several of those in the Downing Street position were already dead...

and at last the Bren ceased its chatter, its last magazine emptied. Churchill reluctantly abandoned the machine-gun, drew his pistol and with great satisfaction, for it was a notoriously inaccurate weapon, shot dead the first German to reach the foot of the steps. As two more rushed forward, covered by a third in the distance, Winston Churchill moved out of the shelter of the sandbags, as if personally to bar the way up Downing Street. A German NCO, running up to find the cause of the unexpected hold-up, recognised him and shouted to the soldiers not to shoot, but he was too late. A burst of bullets from a machine-carbine caught the Prime Minister in the chest. He died instantly, his back to Downing Street, his face toward the enemy, his pistol still in his hand." Excerpt from If Britain Had Fallen by Norman Longmate. Further Reading BBC - History - Hitler plans the invasion of Britain (pictures, video, facts & news) Hitler plans the invasion of Britain Hitler plans the invasion of Britain July 1940 After the invasion and defeat of France in June 1940, Hitler turned his attention to the invasion of Britain, the last country in Western Europe to stand against him.

Photo: Hitler giving his 'Last Appeal to Reason' speech to the German Reichstag at the Kroll Opera House in Berlin, 19 July 1940. (akg-images/Ullstein Bild) Features in: Public reaction to the imminent invasion of Britain Public reaction to the imminent invasion of Britain Frank Scrivener and Bill Pertwee remember how England's southern coast became like a fortress in preparation for the anticipated German invasion. German scepticism about the planned invasion of Britain German naval officers describe their scepticism about the likely success of the planned invasion of Britain. History was part of Churchill's life A.J.P. Taylor describes how Churchill often turned to historical precedents. The credibility of Hitler's speeches Simon Sebag Montefiore explains why Hitler's speeches were so convincing. The historian Simon Sebag Montefiore assesses Hitler's oratorical skills and explains why his rhetoric could have convinced the German people he had 'good' intentions. Ed Murrow Describes the Dunkirk Evacuation Ed Murrow describes the evacuation of Dunkirk. Ed Murrow, the American broadcast journalist, describes the evacuation of Dunkirk, the effect on the British population, and preparations to defend against a German invasion.

More information about: Hitler plans the invasion of Britain "Eliminate the English motherland" Following six weeks of fighting in May and June, France yielded to the Nazi invasion. After the French armistice was signed on 22 June, Britain was the only country resisting Germany. Hitler did not particularly wish to invade Britain; after the fall of France, he assumed the British would simply surrender. Hitler was therefore surprised when Britain did not surrender. On 16 July, he issued 'Directive Number 16'. This authorised detailed preparations for an invasion landing in Britain, codenamed Operation Sealion. It stated: "The aim of this operation is to eliminate the English motherland as a base from which war against Germany can be continued, and, if this should become unavoidable, to occupy it to the full extent". Defeat the RAF, then invade Initially, Directive 16 envisaged a landing along the southern coast of England, from Lyme Regis in Dorset to Ramsgate in Kent. The German navy would contain the Royal Navy in the North Sea and the Mediterranean, and would sweep the English Channel for mines.

Most significantly, the German military leadership agreed that the Luftwaffe must defeat the RAF before the invasion could take place, so that it could not attack the German forces from the air as they were transported across the Channel. German forces planned to begin the air attack on 5 August. They set no specific date for the invasion, as it was dependent on the success of the air battle. However Hitler wanted all preparations to be completed by mid-August. As the Germans now controlled the entire coastline of the North Sea and France, the Luftwaffe were within easy striking distance of most of Britain. Hermann Goering, the head of the Luftwaffe, drew up plans to destroy RAF Fighter Command in just four days. Arrest political leaders, writers and journalists Other preparations for the invasion included locating all available sea and river craft in Germany and training troops in amphibious landings. The Nazis also set out how the occupying German authorities in Britain would be organised. Amongst other tasks they planned to arrest key people who could pose a threat to their regime. The SS’s "Black Book" contained a list of targets, including Churchill and other political leaders, and writers and journalists such as Noel Coward, H.G. Wells and E.M. Forster.

Whilst the Germans savoured their victory over France and began detailing their preparations for the invasion of Britain, the RAF was steeling itself for the critical battle to come. Operation Sealion - planned German invasion of England 1940 Operation Sealion 1946 US invasion of northern Japan Special Forces Operation Sealion Hitler's Directive 16 ordered preparations of a seaborne invasion of England. Operation Sealion ( German : Unternehmen Seelöwe) was the name of the German plan to invade Great Britain in 1940 . An attempt at such an invasion became a realistic possibility following the defeat of France , and the British withdrawal from the continent at Dunkirk . The first German studies for a possible invasion of England across the English Channel, had actually been begun in November 1939 , at which point it was already realized that the major obstacles to German success included the British Royal Air Force (RAF) and the Royal Navy (the latter of which was much stronger than the German Kriegsmarine).

On July 16th 1940 , Adolf Hitler ordered the German military to prepare for the invasion: "Since England, in spite of her hopeless military situation, shows no signs of being ready to come to a compromise, I have decided to prepare a landing operation against England, and if necessary to carry it out". Hitler identified four conditions that needed to be fufilled before the invasion could go ahead: Defeating the RAF Clearing the English Channel of British mines, and using German mines to seal the Straits of Dover. Dominating the coastal zone of (now occupied) France with heavy artillery. Preventing the Royal Navy from intervening in the invasion, by engaging the British fleet in the North Sea and Mediterranean, and by attacking the home squadrons. The Germans Air Force ( Luftwaffe ) soon began Operation Eagle ( German : Unternehmen Adler), which latter became known as the "Battle of Britain": the attempt to defeat and neutralize the RAF. As is well known, the Luftwaffe ultimately failed to reach this objective, and in September of 1940 , switched to bombing London and other British cities instead.

On September 17th 1940 , Hitler cancelled (officially postponed - he hoped to revive the plans, but never did) Operation Sealion. In 1941 , Hitler instead turned to the East, and invaded the Soviet Union ( Operation Barbarossa ) which meant Britain never again faced a serious threat of German invasion. Military historians who have written about the subject , differ about what might have happened had the Germans attempted the invasion, even if they had managed to first obtain air superiority. One view is that they did in fact have a reasonable chance of success, but the other view is that there were so many problems with the German plan , that defeat, possibly even disaster, was inevitable. Another widespread view is that the Germans were never likely to have attempted the invasion, that the plans were not serious, and that they simply hoped to intimidate the British into negotiation or surrender. This idea would certainly be consistent with Hitler's personality - it should be remembered that prior to the outbreak of war (which in July of 1940 had been going on for less than a year), Germany had made a whole series of territorial gains simply by using a combination of threats, bluster and intimidation.

One piece of evidence in support of this theory is that Adolf Galland, who commanded the Luftwaffe's fighter arm at the time, did in fact state after the war that the German invasion plans were never serious. In any case, one thing is for sure, if the Germans successfully carried out Sealion and conquered Britain , the consequences would have been terrible both for Britain and the wider world. Indeed, it is quite possible that German victory over Britain would have ultimately resulted in a German victory in World War II as a whole. Your Comments Please share your comments on this page: Battle of Britain | European history [1940] | Britannica.com European history [1940] Anglo-American Chain of Command in Western Europe, June 1944 Battle of Britain, during World War II , the successful defense of Great Britain against unremitting and destructive air raids conducted by the German air force (Luftwaffe) from July through September 1940, after the fall of France . Victory for the Luftwaffe in the air battle would have exposed Great Britain to invasion by the German army, which was then in control of the ports of France only a few miles away across the English Channel .

In the event, the battle was won by the Royal Air Force (RAF) Fighter Command, whose victory not only blocked the possibility of invasion but also created the conditions for Great Britain’s survival, for the extension of the war, and for the eventual defeat of Nazi Germany . Smoke rising from the London Docklands after the first mass air raid on the British capital, Sept. … New Times Paris Bureau Collection/USIA/NARA Beginning in June 1940 and continuing into the next year, the Battle of Britain was fought in the … Encyclopædia Britannica, Inc. World War II: The Battle of Britain Shortly after the withdrawal of British forces from the European continent in the Dunkirk evacuation (late May–early June 1940), Germany’s armoured forces completed their blitzkrieg invasion of France. The French government collapsed on June 16 and was replaced by a regime that immediately sued for peace. This left the British suddenly alone in their “island home” as the last bastion against “the menace of tyranny,” in the words of their prime minister, Winston Churchill .

Speaking before Parliament on June 18, Churchill announced: What General [Maxime] Weygand [commander of the Allied armies in France] called the Battle of France is over. I expect that the Battle of Britain is about to begin.…Let us therefore brace ourselves to our duties, and so bear ourselves that if the British Empire and its Commonwealth last for a thousand years, men will still say, “This was their finest hour.” An aircraft spotter scanning the skies above London, c. 1940. New Times Paris Bureau Collection/USIA/NARA Members of the London Auxiliary Fire Fighting Services conducting a war exercise, 1939. New Times Paris Bureau Collection/USIA/NARA Similar Topics Battle of Gettysburg On the German side, no plans had been made for an invasion of Britain before the Germans launched their offensive against France, nor were any made even when the collapse of France was assured. German leader Adolf Hitler evidently counted on the British government’s agreeing to a compromise peace on the favourable terms he was prepared to offer, and so he had no desire to press the conflict to a decisive conclusion.

The German army was given to understand that the war was over; leave was granted, and the Luftwaffe was shifted to other quarters. Even when Churchill’s determination to continue the war was made manifest , Hitler still clung to the belief that it was merely a bluff, feeling that Britain must recognize “her militarily hopeless situation.” That hope of his was slow to fade. It was not until July 2 that Hitler even ordered a consideration of the problem of invading England , and he still seemed to doubt its necessity when at last, on July 16, he ordered preparations to begin for such an invasion, christened Operation Sea Lion . Hitler stipulated that the expedition be ready by mid-August. British Culture and Politics The German army was in no way prepared for such an undertaking. The staff had not contemplated it, the troops had been given no training for landing operations, and nothing had been done to build landing craft for the purpose. All that could be attempted was a hurried effort to collect shipping, bring barges from Germany and the Netherlands, and give the troops some practice in embarkation and disembarkation.

The German generals were very apprehensive of the risks that their forces would run in crossing the sea, and the German admirals were even more frightened about what would happen when the Royal Navy appeared on the scene. They had no confidence in their own power to stop the enemy, and they insisted that the responsibility for doing so be placed on the Luftwaffe. Air Marshal Hermann Göring expressed confidence that his planes could check British naval interference and also drive the RAF out of the sky. So it was agreed that Göring would try his preliminary air offensive, which did not commit the other services to anything definite, while the time for the invasion attempt would be postponed to mid-September. Britannica Stories Scientists Ponder Menopause in Killer Whales Beginning with bomber attacks against shipping on July 10 and continuing into early August , a rising stream of air attacks was delivered against British convoys and ports. Then, on August 13, the main offensive—called Adlerangriff (“Eagle Attack”) by Hitler—was unleashed, initially against air bases but also against aircraft factories and against radar stations in southeastern England.

Although targets and tactics were changed in different phases, the underlying object was always to wear down Britain’s air defense, and indeed the effort severely strained the limited resources of Fighter Command, under Air Chief Marshal Sir Hugh Dowding . The British disposed slightly more than 600 frontline fighters to defend the country. The Germans meanwhile made available about 1,300 bombers and dive-bombers and about 900 single-engine and 300 twin-engine fighters. These were based in an arc around England from Norway to the Cherbourg peninsula in northern coastal France. For the defense of Britain, Fighter Command was divided into four groups, of which the most hard-pressed during the Battle of Britain were Number 11 Group, defending southeastern England and London and headquartered at Uxbridge, Middlesex; and Number 12 Group, defending the Midlands and Wales and headquartered at Watnall, Nottinghamshire. The other two groups were Number 10, defending southwestern England, and Number 13, defending northern England and all of Scotland . Each group was divided into sectors, which received reports from group headquarters about approaching Luftwaffe formations and mobilized squadrons of planes from numerous airfields to fight them off.

The British radar early warning system, called Chain Home, was the most advanced and the most operationally adapted system in the world. Even while suffering from frequent attacks by the Luftwaffe, it largely prevented German bomber formations from exploiting the element of surprise. To fight off the bombers, Fighter Command employed squadrons of durable and heavily armed Hawker Hurricanes , preferring to save the faster and more agile Supermarine Spitfire —unsurpassed as an interceptor by any fighter in any other air force—for use against the bombers’ fighter escorts. Supermarine Spitfire, Britain’s premier fighter plane from 1938 through World War II. Quadrant/Flight Facebook Twitter YouTube Instagram Pinterest The British thus found themselves fighting with the unexpected advantage of superior equipment. German bombers (mostly lightly armed twin-engine planes such as the Heinkel He 111 and Junkers Ju 88) lacked the bomb load capacity to strike permanently devastating blows, and they also proved, in daylight, to be easily vulnerable to the British fighters.

The Germans’ once-feared Junkers Ju 87 “ Stuka ” dive-bomber was even more vulnerable to being shot down, and their premier fighter—the Messerschmitt Bf 109 —could provide only brief long-range cover for the bombers, since it was operating at the limit of its flying range. By late August the Luftwaffe had lost more than 600 aircraft and the RAF only 260. Nevertheless, Fighter Command was losing badly needed fighters and experienced pilots at too great a rate to be sustained. Number 11 Group in particular was in a fight for its life—and, by extension, for Britain’s life as well.

Acknowledging that the country’s fate hung on the sacrifice of its airmen, Churchill declared before Parliament on August 20, “Never in the field of human conflict was so much owed by so many to so few.” Britannica Lists & Quizzes BBC - History - World Wars: The German Threat to Britain in World War Two The German Threat to Britain in World War Two By Dan Cruickshank Last updated 2011-06-21 After the surrender of France to Germany in 1940, Britain was the Third Reich's next target. But was invasion imminent or was this part of a strategy? Dan Cruickshank describes the British effort to defend her shores during World War Two. On this page Print this page No surrender When France fell with such rapid speed in June 1940 ten months after the outbreak of World War Two and six weeks after German invasion, Germany believed it had achieved an unprecedented triumph in the most extraordinary conditions. To a large degree, of course, it had.

Traditional enemies and apparently strong opponents had fallen with ease and dramatic speed - not only France, but Poland, Holland, Belgium, Denmark, Norway and Luxembourg had been over run and Britain's army had been outflanked and ejected in late May from Europe with the loss of most of its heavy weapons and equipment. But to Germany's surprise, Britain, although apparently defeated and certainly painfully exposed and isolated, did not surrender. It did not even seek to come to terms with Germany. I have decided to begin to prepare for, and if necessary to carry out, an invasion of England... This was a puzzling state of affairs for the Germans who now had two options: to lay siege to Britain and to wear it down physically and psychologically through limited military action and through political and propaganda warfare, which would include the threat or bluff of invasion; or to actually invade. Both these options demanded that preparations for invasion be launched, whether a real or bluff invasion only time would tell. So, on 16 July 1940 Adolf Hitler issued Directive Number 16.

It read, 'As England, in spite of the hopelessness of her military position, has so far shown herself unwilling to come to any compromise, I have decided to begin to prepare for, and if necessary to carry out, an invasion of England... and if necessary the island will be occupied.' The Germans, surprised by the speed of their military success in Europe, had no detailed plans for an invasion of Britain with the man made responsible for the venture, General Franz Halder, now having to start from scratch. But this absence of a plan did not prevent Hitler from announcing on 16 July that an invasion force would be ready to sail by 15 August. The operation was given the codeword Sealion. Top Operation Sealion The political rather than the military nature of the invasion plan at this time is suggested by the extraordinary timing that Hitler imposed. Planning an invasion and assembling a fleet and appropriate forces in a month was clearly a practical impossibility but timing was an essential part of the game of bluff that Hitler was playing. When the British realised what was coming their way their will to resist would crumble.

From mid July the Luftwaffe stepped up the military pressure by attacking the channel ports and shipping to establish command of the Straits of Dover, while German heavy guns were installed around Calais to bombard the Dover area where the first shells started to fall during the second week of August. By the end of July the Royal Navy had to pull all its larger warships out of the channel because of the threat from German aircraft. All seemed to be going to plan; perhaps this mounting military pressure and the prospect of invasion would break British spirits and make Operation Sealion unnecessary? ...the Royal Navy had to pull all its larger warships out of the channel because of the threat from German aircraft. But by the end of July neither the threat of imminent invasion nor offers by Germany of 'honourable' peace had done the trick. It appeared that Germany would actually have to execute one of the most difficult military operations imaginable: an invasion, launched across at least 20 miles of water, culminating in a landing on a fortified and desperately defended coast line. It was immediately clear that this could not even be attempted until the Royal Navy - still one of the most formidable fighting forces in the world - had been either destroyed or diverted and after the Royal Air Force had been eliminated.

The first reaction of Hitler and the German high command, when it appeared that a real rather than a bluff invasion would have to be organised, was to change the schedule. On the last day of July Hitler held a meeting at the Berghof. He was told of the difficulty in obtaining barges suitable to carry invasion troops and about the problems of massing troops and equipment while the German navy argued for the invasion front to be reduced from the proposed 200 miles (from Lyme Regis in the west to Ramsgate in the east) and for a postponement of the invasion until May 1941. Hitler rejected these requests that, if granted, would have undermined the invasion as a political threat, but the start date was postponed to September the 16th. There is evidence that, during this meeting, Hitler decided that the invasion of England was effectively a bluff operation and that resources should be diverted to the east in preparation for the invasion of the Soviet Union. But, for the bluff to work, the build-up for invasion had to continue and Britain had to be kept under military pressure.

So, after the 31 July meeting it was decided that the Luftwaffe should tighten the screw by attempting to clear the channel of British warships and the skies over southeast England of British aircraft. Hermann Goering saw no problems. The attack was due to start immediately, but bad weather delayed the German air offensive against Britain until 12 August. Top Ironside Two members of the Home Guard © Meanwhile in Britain anti-invasion defences of all types had been planned and executed with incredible speed since late May. At the same time a new force had been organised to help defend the country. The Local Defence Volunteers (LDV) had been raised on 14 May 1940 and comprised men too old or too infirm to join the regular army or in protected trades and thus exempt from conscription. On 23 July, the force became known as the Home Guard, after Churchill coined the phrase during a BBC broadcast. By the end of July one and a half million men had volunteered, a huge figure which reveals the seriousness with which ordinary people took the threat of invasion in the summer of 1940.

Ironside's only option was to set up a static system of defence which, he hoped, could delay German invasion forces after landing... On 27 May Churchill had put General Sir Edmund Ironside, Commander-in-Chief Home Forces, in charge of organising Britain's defence. Ironside acted quickly. He had a large force at his disposal, but one that was poorly armed and equipped and generally poorly trained. In the circumstances, Ironside's only option was to set up a static system of defence which, he hoped, could delay German invasion forces after landing and so give Britain time to bring its small mobile reserves into play. If the Germans could be delayed on the beaches and then delayed as they pushed inland their timetable could be thrown off balance, they could lose impetus, direction and initiative and the British army might be able to counter attack effectively. The key to Ironside's pragmatic plan was defence in depth. Southeast England was to offer a series of barriers or stop-lines formed by concrete pillboxes, gun emplacements, anti-tank obstacles, trench systems, minefields and barbed wire entanglements and utilising natural and man-made features such as rivers, canals and railway embankments. They were to ensnare and delay the German forces.

The Germans, of course, had their own script for the battle and their detailed air reconnaissance of Britain in early 1940 meant that the stop-lines would have held few surprises for the attackers. But, whatever happened, Ironside was determined that this would be a battle of attrition. At the very least the Germans would be made to bleed before they achieved their objectives. By 25 June, Ironside's anti-invasion plan was complete and presented to the War Cabinet as Home Forces Operations Instruction Number 3. This Instruction gave detail to Ironside's defence theory. There was to be a coastal 'crust' that was to consist of a thin screen of infantry deployed along the beaches. This crust was to disrupt enemy landings long enough to allow the arrival of local reinforcements. Behind the coastal crust a network of stop-lines of various strengths and significance were constructed to slow down and contain or channel any German advance. The final and main position of resistance was the General Headquarters Anti-tank Line (the GHQ stop-line). This was the backbone of Ironside's coordinated defence plan.

The line was planned to stretch from around Bristol in the west then east to Maidstone and running south around London passing just south of Guildford and Aldershot, then northeast to the Thames Estuary. Then beyond that, through Cambridge and the fens and up the length of England, running inland parallel with the east coast but able to defend the major industrial centres of the midlands and the north, and up to central Scotland. An auxiliary GHQ line was also to be established around Plymouth. Top A revised invasion plan The production of component parts for Spitfire aircraft. © During August, as the stop-lines were nearing completion, the Luftwaffe's battle for the control of the air over England and the channel continued. But the assault on the RAF started to go awry as Goering changed the emphasis of attack from radar stations and airfield to aircraft factories and more peripheral targets - thus giving RAF front line squadrons a much needed breathing space. While what became known as the Battle of Britain started to reach its crescendo, the debate about Operation Sealion also continued to rage during August between the German navy and the army.

A meeting on 7 August revealed irreconcilable differences: 'I utterly reject the Navy's proposals [for landing on a narrow front],' exclaimed General Halder. 'I might just as well put the troops through a sausage machine.' Eventually a compromise was reached. On 13 August, Hitler agreed that the invasion front should to be narrowed, with the most westerly landing area being around Worthing. This meant that the only one German Army Group - Army Group A - would carry out the invasion. The revised invasion plan was issued by the German High Command on 30 August. ...Hitler agreed that the invasion front should to be narrowed, with the most westerly landing area being around Worthing. The attack group of the 9th Army (Part of Army Group A) was to leave from Le Havre and land in the Brighton-Worthing area of Sussex. The first assault wave was to secure the beachhead. The second wave packed the real punch for it was made up of two Panzer Divisions - each composed of tanks, artillery, mobile troops and Panzer grenadier assault infantry - and one motorised division. The role of the panzers was to break out of the beachhead and then sweep west towards Portsmouth.

The attack group of the 16th Army (also part of Army Group A) was to leave from the Calais-Ostend-Antwerp area and land in the Folkstone-Dungeness area around Rye and at Bexhill-Eastbourne. The first wave here was to consist of two infantry divisions, while the second wave was to include two Panzer Divisions that were to break out of the beachhead and advance north - to destroy the main reserves of the British army and establish crossings over the River Medway. These landings were to be supported by parachute troops, who were to drop on the Downs above Brighton, to assist in the securing of the beach head for the Brighton-Worthing assault group, and north west of Folkestone in Kent to seize the Royal Military Canal of Napoleonic war vintage. The Germans saw this canal, which had been built to stop French invaders storming across Romney Marsh on their way to London, as a significant anti-tank obstacle that could, if not bridged, stall the advance of their panzers. Top The ultimate target The initial objective for both assault groups was to establish a front from the Thames Estuary to Portsmouth. Then the build-up would begin with additional supplies and troops being brought in.

When the build-up was complete the panzers of the Brighton-Worthing assault group would attack towards Basingstoke, Newbury and Oxford to secure crossing points over the Thames and to encircle and isolate London and the southeast in a great pincer movement. The remaining German forces, located around the Medway and on the Thames estuary, would then thrust towards London - the ultimate target of the invasion force. The remaining German forces, located around the Medway and on the Thames estuary, would then thrust towards London... General von Runstedt was in command of Army Group A, which was to be the main tool of invasion. As it happened, Von Runstedt had little faith in Halder's Sealion plan. He observed that Napoleon had failed to invade and the difficulties that confounded him did not appear to have been solved by the Sealion planners. Probably von Runstedt observed that one of the plan's main weaknesses was the small scale of the initial assault and the slow build-up. The first wave assault was to be carried out not by nine complete divisions but only their leading echelons numbering in each case around 6,700 men.

So only the equivalent of three divisions - around 60,000 men - would have been involved in the first wave assault. About 250 tanks and very little artillery would have supported them. An added factor worrying von Runstedt would no doubt have been the amateur and ad-hoc nature of the sea transport. The consequence would be troops landed at the wrong place or at the right place at the wrong time - or not landed at all if British sea and air power had not been completely destroyed. And these same problems of transport would apply to and slow down the build-up of reinforcements unless a number of major ports were captured quickly and intact - which was highly unlikely. Top German defeat RAF pilots © Hitler appeared to agree with von Runstedt when, on 14 August - the day after he had agreed a narrower invasion front - Hitler told his generals that he would not attempt to invade Britain if the task seemed too dangerous. There were, said Hitler, other ways of defeating Britain. As Hitler started to back away from invasion the battle for dominance of the skies over England and the English Channel - a battle that now, perhaps, had little strategic value - reached a new peak of fury.

On 3 September, with the RAF still far from destroyed, Field Marshal Keitel, head of the Armed Forces High Command, delayed Sealion until 21 September, and then again until 27 September, the last time the tides would be right before the end of the year. The day after this last postponement was announced, Goering launched his final major offensive to destroy RAF Fighter Command in daylight action. It was a dismal failure, with the Luftwaffe losing twice as many aircraft as its potential victim. On 17 September - two days after Goering's defeat - Operation Sealion was postponed indefinitely. The plan was never to be revived. Hitler's attention was drawn increasingly to the east, and in June 1941 he invaded the Soviet Union. In 1944 Britain's defences against sea-borne attack were scaled down. In 1944 Britain's defences against sea-borne attack were scaled down. By that date it was finally certain that the German army - fatally mauled in Russia - was in no position to invade Britain. But Britain's coastal defences were not dismantled.

As the war ended, there were those who believed that the Soviet Union would be the next enemy and in anticipation of this NATO was formed in 1947 for the defence of western Europe and north America. But even if the Soviets were the new enemy it gradually became clear during the early 1950s that a Soviet invasion - if it came - would not be launched against the coast of Britain, and from 1956 coastal defences around the British Isles were gradually decommissioned.

Find out more Books Twentieth Century Defences in Britain: An Introductory Guide by I Brown et al (Council for British Archaeology, 1995) The Defenders: A History of the British Volunteers by G Cousins (Muller, 1968) Invasion: From the Armada to Hitler, 1588-1945 by F McLynn (Routledge and Keegan Paul, 1987) The Air War, 1939-1945 by RJ Overy (Europa Publications, 1980) Channel Defences by A Saunders (Batsford/English Heritage, 1997) Resisting the Nazi Invader by A Ward (Constable, 1997) Pillboxes: A Study of UK Defences, 1940 by H Wills (Leo Cooper, with Secker and Warburg, 1985) Links The Fortress Study Group . This is the only international society concerned with the study of all aspects of military architecture and fortifications and their armaments, especially works constructed to mount and resist artillery. Places to visit Duxford Aviation Museum .

Telephone: 01223 835 000. Duxford is home to 180 historic aircraft, including biplanes, Spitfires, Concorde and fighter jets. RAF Air Defence Radar Museum . Royal Air Force, Neatishead, Norwich, Norfolk, NR12 8YB. Tel: 01692 633309. The museum holds original Unit and Station badges, a model aircraft collection and a large quantity of photographs, documents and videos relating to Air Defence equipment. Top About the author Dan Cruickshank is one of the country's leading architectural and historic building experts and a regular presenter on the BBC. He is an active member of the Georgian Group and the Architectural Panel of the National Trust and director of the Spitalfields Historic Buildings Trust. Dan is a frequent contributor to The Architects' Journal and The Architectural Review and is author of Life in The Georgian City and The Guide to the Georgian Buildings of Britain and Ireland. Operation Sealion - History Learning Site Operation Sealion Citation: C N Trueman "Operation Sealion" historylearningsite.co.uk. The History Learning Site, 20 Apr 2015.

16 Aug 2016. Operation Sealion was the name given by Hitler for the planned invasion of Great Britain in 1940. Operation Sealion was never carried out during the war as the Germans lost the Battle of Britain and it is now believed that Hitler was more interested in the forthcoming attack on Russia as opposed to invading Britain. Göering, on right, overlooking the White Cliffs of Dover The projected invasion on Britain included: Army Group A (6 divisions) invading Kent via the areas near Ramsgate, Folkstone and Bexhill Army Group A (4 divisions) invading Sussex and Hampshire via the area around Brighton and the Isle of Wight. Army Group B (3 divisions) invading Dorset via Lyme Bay From Kent, Army Group A would advance to south-east London and then to Malden and St. Albans north of London. From Sussex/Hampshire, the 4 divisions of Army Group A would advance to the west of London and meet up with the other 6 divisions of Army Group A, thus encircling London. Other parts of the group would head towards Gloucester and the River Severn region. From Dorset, Army Group B would advance to Bristol.

The whole plan relied on Germany having complete control of the English Channel, which, in turn meant that Germany had to have control of the skies so that the Royal Air Force could not attack German ships crossing the Channel. Hence victory in the Battle of Britain was an integral part of the plan. Operation Sealion looked simple in theory. Britain should have been an easy target. The Luftwaffe was very experienced in modern warfare, the Wehrmacht had experienced astonishing success since the attack on Poland and the British had lost a vast amount of military hardware on the beaches of Dunkirk. The RAF and the Army in Britain looked weak; only the Royal Navy seemed to offer Britain some semblance of protection. It is said that Hitler was prepared to offer Britain generous peace terms. However, on May 21st, 1940, Admiral Raeder told Hitler about a plan to invade Britain and Hitler, it is said, was taken in by the plan. If Britain had not surrendered, Hitler had planned an economic war which could have taken a long time to be effective. However, a military conquest of Britain would be swift and decisive.

The military success of the German military since September 1939, seem to confirm in Hitler’s mind that an attack on a demoralised British Army would be swift. Towards the end of June 1940, Hitler gave the order for the German military to make plans for an invasion of Britain. In fact, they were one step ahead of Hitler here as all three branches of the German military had guessed that an invasion would be needed and had already started on their own plans. In November 1939, the German Navy had done its own report on an invasion of Britain. It was not optimistic about its success. The German Navy detailed many problems that would be experienced for either a short crossing or a long crossing. It did not state that an attempted invasion would be unsuccessful – but it was cautious. In December 1939, the Wehrmacht had produced its own report. This favoured a surprise attack on Britain via East Anglia by 16 or 17 divisions. However, this plan needed the support of the German Navy and they believed that the Wehrmacht’s plan was untenable as the German navy would have to protect any landing fleet of the army whilst having to fight the British Navy.

Raeder believed that this was an impossible task to complete successfully. The Luftwaffe pointed out that for its part, it would need good weather for the whole of the invasion if it was to do its job – and across the North Sea this could not be guaranteed. Though the Luftwaffe had experienced success in both the attacks on Poland and Western Europe, the RAF had not used its fighter force to its full capacity in the spring of 1940. After the fall of France, the only major European power not to have fallen was Great Britain. The problems of an invasion were known to all three branches of the German military: Control of the Channel would be needed Control of the skies would be needed Good weather would be needed However, for all of the work done by the military on a projected invasion of Britain, it seems that Hitler had little enthusiasm for it. On June 17th, 1940, the navy received a communiqué that informed them that: “With regard to the landing in Britain the Führer has not up to now expressed such an intention, as he fully appreciates the unusual difficulties of such an operation.

Therefore, even at this time, no preparatory work of any kind has been carried out in the Wehrmacht High Command.” On June 21st, 1940, the navy was told that the Army General Staff: “Is not concerning itself with the question of England. Considers execution impossible. Does not know how the operation is to be conducted from the southern area.” Hitler’s position was obviously crucial as without his support no invasion was possible. At the time, it is thought that he believed that Britain would sue for peace and that he could make generous peace terms with the British on the condition that they recognised Germany’s position on mainland Europe. Even during the Dunkirk evacuation, one of his generals – Blumentritt – was astonished to hear Hitler talk about the British in glowing terms. “(Hitler spoke) with great admiration of the British Empire, of the necessity for its existence, and of the civilisation that Britain had brought into the world.” Blumentritt It was only when it became clear that Britain would not sign peace terms that Hitler gave his backing to an invasion. On July 2nd 1940, Hitler gave his first tentative orders regarding a possible invasion of Britain.

It stated that “a landing in England is possible, providing that air superiority can be attained and certain other necessary conditions fulfilled…..all the preparations must be made on the basis that the invasion is still only a plan, and has not yet been decided upon.” Hitler, July 2nd 1940 On July 13th, the army chiefs presented their plan – see first box above. They were so confident of success that they believed that Britain would be occupied within a month. On July 16th a directive called ‘Preparation for a landing operation against England’ was issued which stated that “As England, in spite of her hopeless military situation, still shows no willingness to come to terms, I have decided to prepare, and if necessary, to carry out, a landing operation against her. The aim of this operation is to eliminate the English mother country as a base from which the war against Germany can be continued, and, if it should be necessary, to occupy it completely.” The code name for this operation was ‘Sea Lion’.

At a meeting with his service chiefs on July 21st, Hitler made it clear that he recognised that the plan had its dangers – especially those identified by Raeder – but he was keen to press on with the plan so that he could turn his full attention to Russia once Britain had been defeated. Hitler wanted Sea Lion to be over by mid-September. His naval chiefs believed that any invasion could not start until mid-September! Raeder supplied a list of reasons why the invasion could not go ahead before mid-September1940 (clearance of shipping lanes of mines, getting invasion barges ready etc) and he won the support of the army. Hitler ordered that as long as Germany controlled the sky, Operation Sea Lion would go start on September 15th 1940. Therefore, the invasion depended entirely on whether Göering’s Luftwaffe could defeat the RAF. The failure of the Germans to defeat the RAF had to lead to the cancellation of Operation Sea Lion which was announced on September 17th 1940. One of the interesting issues to come out of this episode was the inability of the three units that made up the German military to either work together or support one another.

primarily, the chiefs of the army railed against Raeder while he and his chiefs criticised the plans of the army. The Luftwaffe took the view, though it was primarily Göering’s, that any success depended on the Luftwaffe conquering the skies. Another key point that came out of this episode in the war, was Hitler’s seeming refusal to listen to his military commanders and wanting things done his way. This came out of the success the military had against Poland and the nations of Western Europe – countries attacked without the overwhelming support of the military but attacked because Hitler instinctively knew that they would win – or so he believed.

Question: What was the German codename for the proposed invasion of Great Britain in 1940 ?
Answer: OPERATION SEALION