Friday, 29 November 2013

Could Britain have Repelled A German Invasion In 1940?

One of then greatest questions discussed by historians for decades; Could Britain have repelled a numerically superior and better trained armed forces if Germany had invaded in 1940?

I have to answer yes, even though many people including my Father (God bless him) would disagree. Why do I chose to disagree? There is plenty of evidence to suggest that a German invasion, would have failed.

One also has to assume that Germany had sufficient transport for its infantry ( landing craft and JU-52 transport aircraft) as in 1940 it had neither.
As is well documented, the British Expeditionary Force (together with Belgian and French soldiers) were evacuated from France in May-June 1940, the majority of which were evacuated form the port of Dunkirk. There was very little in the way of equipment taken back to Britain as space was too valuable on board the boats and ships, indeed most of the troops did not posses a rifle.

After Dunkirk and other evacuations including Cherbourg Brest and St Lo,what did Britain posses to repel German troops? Britain had witnessed the much feared German blitzkrieg scythe through Europe. France would capitulate by June 22nd. 1

With the three main branches of the German armed forces working in cooperation with each other and not competing Operation Sea Lion could have taken place. Would an invasion have been successful? Fortunately we shall never know. One thing is certain however, a German victory would not have been easy or quick, unlike the relatively easy victories of the Low Countries and Denmark.

Britain had learned a valuable lesson in the Battle of France- not to rely on fixed defensive lines like those of the Maginot Line. France and Britain were still using tactics from the First World War whereas Germany had developed blitzkrieg (lightning war). Attacks with strength and speed were used, dive bombing Stukas with deafening sirens, closely followed by tanks and armoured personnel carriers and infantry. Germany had learned from the mistakes of the 1914-1918 war, whereas it's enemies had not. Fixed defences with all the guns pointing in one direction proved to be a complete failure. Airborne troops and glider troops proved this system of defence to be obsolete. There were also gaps in the line, at the Belgian border and the Ardennes. The Ardennes was said to be impenetrable, and then used by the Germans for their main armoured thrust in 1940.

What Defences Were Used By Britain For Home Defence?

Britain used many methods of defence whilst awaiting an invasion. The problem was forecasting where the invasion was going to arrive. It was impossible to forecast this without good intelligence, so Britain had to expect to be attacked on the southern and south eastern coasts as this was the shortest route from occupied France. In fact most of the coastline would be defended by some means, if only by barbed wire.

The most obvious defence was the English Channel. As the Germans were not prepared for an assault by the sea, they lacked landing craft and their navy was much smaller than that of the Royal Navy. The German plan was to transport men and horses across the English Channel using towed barges. Unless the Royal Air Force was defeated, this would mean some of the crossing would have to take place in darkness, seriously affecting the ability of the Luftwaffe to defend an invasion fleet. The darkness would work in the favour of the Royal Navy however, it would only take one destroyer going at full speed ahead to sink these barges by its wash alone, without firing it's guns.

(Image of barbed wire beach defences found at: ).

Barbed wire, would be the next form of defence as previously stated, it would be laid across the beaches in varying depths, this would ensure the defenders would be able to easily pick off the Germans as they landed, in 1940 there was no way through it other than wire cutters. The wire and minefields would be covered by soldiers in trenches and pillboxes. Unlike the Maginot Line, this was not designed to be the only defence, there would be more lines of defence further inland. Ironside had been put in charge of British defence on the 27th May 1940 and realised that delaying the Germans would be the order of the day. If they suffered enough delays to their objectives, it would give the British forces enough time to re-group and re- organise for a counter attack2. Fields were cluttered with obstacles to prevent glider landings. Bridges were guarded., road signs removed to confuse the enemy. Parts of East Anglia had been flooded including Romney marsh, more would be flooded to slow down a German advance when the Germans invaded.

(Coast tank trap defences, image found at: )

Tanks traps,hedgehogs and dragons teeth would also have some effectiveness in slowing down an armoured advance, assuming the Germans could transport them across the Channel. It is doubtful that anti-tank defence would have ever been needed if what Robinson wrote is to be believed. He claims that the Germans were not planning to bring tanks in any quantity, or vehicles. They were to rely on horses, 125,00 of them3. Horses do not repel bullets, need feeding and are slow compared to other vehicles. The German army high command did not want to transport fuel, or rely on capturing British fuel dumps.

How many troops did Britain have ready to fight in 1940? Over 300,000 were evacuated from Dunkirk in 1940, more from other ports such as Brest ,St Lo and Cherbourg took the total to over 500,0004.These troops would need to be rested and re-equipped before being put on an active role again. Local Defence Volunteers were formed on 14th May 19405, men who were too young or old could enrol and take part in defending their local town or village. They were later renamed the Home Guard and by the end of June 1940 they numbered more than 1,400,0006. The Home Guard was at first very badly equipped, having to use personal firearms, Molotov cocktails, pickaxe handles and even improvising pikes. They had no uniform at first, just an LDV armband, and these were home-made. Putting these inadequacies to one side, they would serve two purposes: They would attract men who could otherwise get in the way of the regular forces, should an invasion come. Being part of the armed forces would mean they could not be like partisans. Also. they would significantly contribute to the delay needed for the armed forces to regroup, and then counter attack.

Auxiliary Units were to be used after the invasion had passed through their area. They were ordinary people who would operate in civilian clothes. When the invasion happened they would hide out in specially made bunkers, often camouflaged in woods and perform various tasks. These included sabotaging any German vehicles, reporting German movements by radio to the military and relaying messages. The saboteurs among them were to fight with guns and explosives until their ammunition ran out, then if they were still alive, disband and go back to their own homes.

As a last resort, gas was to be used on the Germans. Churchill had authorised this in 1940, gas was to be sprayed on German troops by Fairey Battle aircraft. This may seem drastic nowadays, but what choice did Churchill have? There was nowhere left to evacuate to and he knew the Germans had to be stopped.

The Germans were planning to land at least 160,000 troops off the English coast. It is necessary to use one's imagination at this point. Germany had troops, tanks and horses but no way of transporting them quickly over the English Channel. The Germans planned to use steamers and tugs towing barges, Robinson states that there would be nearly 1000 barges towed across the Channel7. Obviously such transport was completely inadequate and unsuitable for such a task. An armed escort would consist of a total of 8 destroyers and numerous E-boats8. Opposing this invasion fleet would be at least 44 destroyers and cruisers9, (this does not take into account the British submarine fleet or U-boats). Even the most biased of opinions cannot be swayed by these facts. The German invasion fleet would have at least suffered a severe mauling.

Airborne troops had been used by the Germans in Holland to capture bridges and airfields. They also knocked out the Belgian fort at Eben Emael. They proved useful in surprise attacks behind the front line, but were far from invincible. The problem for Sea Lion would be shortage of transport aircraft (Ju-52), and the lack of heavy weapons. Airborne troops could carry only light weapons and mortars, which would make them unable to resist a determined counter-attack. JU-52's were generally unarmed, and would prove easy meat for fighter aircraft.

Assuming the Germans got ashore, they would be outnumbered, unable to land in strength due to the transportation problems and under attack from both land and air as the Royal Air Force proved impossible to defeat. The landing barges could only be unloaded from the stern, they were slow and would ride very low in the water. This would involve some manoeuvring, which would take time and make these makeshift landing craft easy targets for the coastal defences, the RAF and the Royal Navy. The RAF had provided air cover at the evacuation of France. It was not perfect, ships and troops were often under attack on the beaches, but the fact remains that because of the RAF nearly half a million troops escaped to Britain to fight again.

The longer Hitler and his forces delayed meant that more defences would be built, more men trained and more equipment would be made in British factories. Large quantities of supplies began to arrive from the United States and Canada. On 9th July 200,000 rifles from the U.S.A10. 75,000 Ross rifles were on their way from Canada11. Britain had also bought the entire production of the Thompson Machine Co of Chicago – 5,000 machine guns a month12. This would replace weapons lost in France, and ensure the Home guard was armed properly. Eventually ,Britain received re-conditioned American destroyers ( at least 50)in exchange for bases in British Colonies such as Trinidad, Bermuda and St Lucia.

The Germans concentrated on aerial domination , there is no need to go into great detail about the Battle of Britain. It is widely known that the Germans could not defeat the RAF, and were unwilling to cross the Channel until the RAF had been defeated by the Luftwaffe. By the time the Battle of Britain had ended it was September, which meant a rougher Channel crossing for an improvised invasion fleet, and shorter daylight hours, which could mean no air cover for an invasion fleet. This would leave it exposed to the Royal Navy destroyers.

Assuming half the troops and horses landed safely what would happen then? They would be under constant fore from beach defences. They would have to advance through barbed wire and minefields. Those that survived all this would have to wipe out the soldiers in the trenches and pillboxes and then fight reinforcements that would inevitably arrive. They would have to advance inland to meet up with airborne troops that would have been dropped before the invasion fleet landed. How effective these troops would have been remains doubtful. Transports would be shot down before and after dropping their paratroops. They were only lightly armed and may soon need rescuing themselves. Unlike the attacks on Denmark Holland and Belgium the British troops were on a high state of alert. Home Guard and Auxiliary troops would have slowed the German advance further while the main British forces retreated and regrouped. The Royal Navy would be attacking the German fleet, alongside the RAF. What was the chance of German success, even if they had got ashore? None. Even if they had made progress, there is no doubt the British military would have used gas on the invader. The results of this could be catastrophic but Churchill would have used every weapon available to defeat a German invasion force.


Gilbert, M, The Second World War.
Robinson, D, (2005), Invasion 1940 London.


The World At War, (1973), Thames television. The episode Alone is particularly relevant to this essay.


British Resistance Archive, found at: .

McCann, G, The Home Guard and Dad's Army, found at: .

Cruickshank, D, The German Threat To Britain In World War 2, found at: .

British Resistance Archive, found at: .

Walberswick Coastal Defences Of World War 2, found at: .


2The German Threat To Britain In World War 2, Cruickshank, D, found at: .
3Robinson D, Invasion 1940, p.127.
5The Home Guard and Dad's Army, McCann,G, found at:
7Robinson, D, xi.
8Ibid, x, xi.
10Robinson, p.105.
11Ibid, p.106.

13, Just found this online, 12.6.15, Just found this online, the results of a Sandhurst College wargame in 1974. Adolf Galland, Friedrich Ruge and Heinrich Trettner took part. Operation Sealion - summary of an exercise held at the Staff College, Sandhurst in 1974. This can be found at:
The full text is in 'Sealion' by Richard Cox. The scenario
is based on the known plans of each side, plus previously
unpublished Admiralty weather records for September 1940.
Each side (played by British and German officers respectively)
was based in a command room, and the actual moves plotted
on a scale model of SE England constructed at the School
of Infantry. The panel of umpires included Adolf Galland,
Admiral Friedrich Ruge, Air Chief Marshal Sir Christopher
Foxley-Norris, Rear Admiral Edward Gueritz, General Heinz
Trettner and Major General Glyn Gilbert.

The main problem the Germans face is that are a) the
Luftwaffe has not yet won air supremacy; b) the possible
invasion dates are constrained by the weather and tides
(for a high water attack) and c) it has taken until
late September to assemble the necessary shipping.

FJ = Fallschirmjaeger (German paratroops)
MTB = Motor Torpedo Boat (German equivalent, E-Boat)
DD = Destroyer
CA = Heavy Cruiser
BB = Battleship
CV = Aircraft Carrier

22nd September - morning
The first wave of a planned 330,000 men hit the beaches
at dawn. Elements of 9 divisions landed between
Folkestone and Rottingdean (near Brighton).
In addition 7th FJ Div landed at Lympne to take the airfield.

The invasion fleet suffered minor losses from MTBs during
the night crossing, but the RN had already lost one
CA and three DDs sunk, with one CA and two DDs damaged,
whilst sinking three German DDs. Within hours of the landings
which overwhelmed the beach defenders, reserve formations
were despatched to Kent.  Although there were 25 divisions
in the UK, only 17 were fully equipped, and only three
were based in Kent, however the defence plan relied on
the use of mobile reserves and armoured and mechanised
brigades were committed as soon as the main landings were

Meanwhile the air battle raged, the Luftwaffe flew 1200
fighter and 800 bomber sorties before 1200 hrs. The RAF
even threw in training planes hastily armed with bombs,
but the Luftwaffe were already having problems with their
short ranged Me 109s despite cramming as many as possible
into the Pas de Calais.

22nd - 23rd September
The Germans had still not captured a major port, although
they started driving for Folkestone. Shipping unloading
on the beaches suffered heavy losses from RAF bombing
raids and then further losses at their ports in France.

The U-Boats, Luftwaffe and few surface ships had lost
contact with the RN, but then a cruiser squadron with
supporting DDs entered the Channel narrows and had to
run the gauntlet of long range coastal guns, E-Boats
and 50 Stukas. Two CAs were sunk and one damaged. However
a diversionary German naval sortie from Norway was
completely destroyed and other sorties by MTBS and DDs
inflicted losses on the shipping milling about in the
Channel. German shipping losses on the first day
amounted to over 25% of their invasion fleet, especially
the barges, which proved desperately unseaworthy.

23rd Sept dawn - 1400 hrs.
The RAF had lost 237 planes out 1048 (167 fighters and
70 bombers), and the navy had suffered enough losses such
that it was keeping its BBs and CVs back, but large
forces of DDs and CAs were massing. Air recon showed a
German buildup in Cherbourg and forces were diverted to
the South West.

The German Navy were despondant about their losses,
especially as the loss of barges was seriously
dislocating domestic industry. The Army and Airforce
commanders were jubilant however, and preperations for
the transfer of the next echelon continued along with
the air transport of 22nd Div, despite Luftwaffe losses
of 165 fighters and 168 bombers. Out of only 732 fighters
and 724 bombers these were heavy losses. Both sides
overestimated losses inflicted by 50%.

The 22nd Div airlanded successfully at Lympne, although
long range artillery fire directed by a stay-behind
commando group interdicted the runways. The first British
counterattacks by 42nd Div supported by an armoured
brigade halted the German 34th Div in its drive on Hastings.
7th Panzer Div was having difficulty with extensive
anti-tank obstacles and assault teams armed with sticky
bombs etc. Meanwhile an Australian Div had retaken
Newhaven (the only German port), however the New Zealand
Div arrived at Folkestone only to be attacked in the
rear by 22nd Airlanding Div. The division fell back on
Dover having lost 35% casualties.

Sep 23rd 1400 - 1900 hrs
Throughout the day the Luftwaffe put up a maximum effort,
with 1500 fighter and 460 bomber sorties, but the RAF
persisted in attacks on shipping and airfields. Much of
this effort was directed for ground support and air
resupply, despite Adm Raeders request for more aircover
over the Channel. The Home Fleet had pulled out of air
range however, leaving the fight in the hands of 57 DDs
and 17 CAs plus MTBs. The Germans could put very little
surface strength against this. Waves of DDs and CAs
entered the Channel, and although two were sunk by U-Boats,
they sank one U-Boat in return and did not stop. The German
flotilla at Le Havre put to sea (3 DD, 14 E-Boats) and at
dusk intercepted the British, but were wiped out, losing
all their DDs and 7 E-Boats.

The Germans now had 10 divisions ashore, but in many
cases these were incomplete and waiting for their
second echelon to arrive that night. The weather
was unsuitable for the barges however, and the decision
to sail was referred up the chain of command.

23rd Sep 1900 - Sep 24th dawn
The Fuhrer Conference held at 1800 broke out into bitter
inter-service rivalry - the Army wanted their second
echelon sent, and the navy protesting that the
weather was unsuitable, and the latest naval defeat
rendered the Channel indefensible without air support.
Goring countered this by saying it could only be done
by stopped the terror bombing of London, which in turn
Hitler vetoed. The fleet was ordered to stand by.

The RAF meanwhile had lost 97 more fighters leaving only
440. The airfields of 11 Group were cratered ruins, and
once more the threat of collapse, which had receded in
early September, was looming. The Luftwaffe had lost
another 71 fighters and 142 bombers. Again both sides
overestimated losses inflicted, even after allowing for
inflated figures.

On the ground the Germans made good progress towards Dover
and towards Canterbury, however they suffered reverses
around Newhaven when the 45th Div and Australians
attacked. At 2150 Hitler decided to launch the second wave,
but only the short crossing from Calais and Dunkirk. By
the time the order reached the ports, the second wave
could not possibly arrive before dawn. The 6th and 8th
divisions at Newhaven, supplied from Le Havre, would not
be reinforced at all.

Sep 24th dawn - Sep 28th
The German fleet set sail, the weather calmed, and U-Boats,
E-Boats and fighters covered them. However at daylight 5th
destroyer flotilla found the barges still 10 miles off
the coast and tore them to shreds. The Luftwaffe in turn
committed all its remaining bombers, and the RAF responded
with 19 squadrons of fighters. The Germans disabled two
CAs and four DDs, but 65% of the barges were sunk. The
faster steamers broke away and headed for Folkestone,
but the port had been so badly damaged that they could
only unload two at a time.

The failure on the crossing meant that the German
situation became desperate. The divisions had sufficient
ammunition for 2 to 7 days more fighting, but without
extra men and equipment could not extend the bridgehead.
Hitler ordered the deployment on reserve units to Poland
and the Germans began preparations for an evacuation as
further British arracks hemmed them in tighter. Fast
steamers and car ferries were assembled  for evacuation
via Rye and Folkestone. Of 90,000 troops who landed
on 22nd september, only 15,400 returned to France, the rest
were killed or captured.