Operation Sealion: Hitler's Plan to Invade England

German HE 111 bomber over London, 1940
Photo from Wikimedia Commons 
and Imperial War Museum

By Adrian McGrath

The Germans had a song from a poem called

“Wir fahren gegen Engeland.”  

In English this meant “We move against England.”
It was about a German sailor from World War I
who romantically had
one last drink with his comrades,

kissed his girlfriend goodbye, then ventured
off heroically to fight

the English.

The song became a rousing, upbeat tune, a march

designed to encourage the soldiers on to yet another
quick and spectacular victory

for the Wehrmacht, the German arms forces,
and the Kriegsmarine, the German Navy.

British soldiers fighting at Dunkirk, 1940
Photo from Wikipedia and the
Australian War Museum 

After defeating and occupying Poland, Denmark, Norway,

Belgium, Holland, and most impressively, France in a

Lightning War called Blitzkrieg, the Germans must have

felt invincible. The Germans' song about attacking
England seemed a perfect fit.

British Prisoners of War next
to a German panzer tank in
 Calais, France 1940
  Photo fromWikimedia Commons
and German Federal Archives

Since September of 1939 until June of 1940, the Nazi armies

had seen nothing but victory. The Soviet Union, a potential

enemy Hitler hated and feared, had suddenly been

neutralized by Hitler's cynical diplomacy, a mutual

non-aggression pact. Stalin and Hitler were now, more or

less, at peace with each other. Poland and France,

Hitler's enemies in the war so far, were both defeated.

Only Britain was left.

The British Army and some French troops were

miraculously evacuated at Dunkirk and brought back

to England. The soldiers were saved, but their heavy

equipment was lost, and the troops were beaten down

and demoralized.

The English Channel.
Note the short distance between Calais and Dover,
only about 33 miles. But the rough waters can be treacherous.
Photo from NASA satellite and Wikimedia Commons

All that stood between the Germans and a likely British

defeat, it seemed, was the treacherous English Channel

and a stubborn and defiant British leader named

Winston Churchill.

Winston Churchill
Photo from
Wikimedia Commons 

Operation Sealion was the German plan to invade

England. Hitler always had his mind on the East; he

wanted what he called Lebensraum or living space

for Germany, vast lands, resources, and enslaved

populations for Germany’s expansion. He wanted,

therefore, to attack Russia.

Adolf Hitler (left)
and Hermann Goering,
head of the Luftwaffe,
German air force. Berlin, 1938
Photo from Wikipedia 

But now Hitler in the summer of 1940 was facing

England alone.

Hitler was hesitant to invade Britain, wanting instead

a negotiated peace whereby Britain would give Germany

a free hand in Europe and become something of an ally,

a puppet, or at least a neutral of Germany’s.

Improvised German landing craft
The Germans lacked ships and
proper landing craft for Sealion.
Photo from Wikipedia
and German Federal Archive

But Hitler would not get a puppet in Winston Churchill who

vowed to “fight on the beaches” to the very end. So,

Hitler allowed for the initial steps of Sealion to go forth.

On July 16, 1940 Hitler ordered his military commanders to

draw up plans for the amphibious invasion of Britain called

in German Seelowe or in English Sealion. It would be

incredibly complex involving air, sea, and ground forces.

Target date for Sealion was September 15. This gave the

Germans only two months to prepare.

By October the weather and

seas in the English Channel would be so rough that an

amphibious invasion would be out of the question.

As was later learned when the Allies invaded France at

Normandy in 1944, several things were absolutely necessary

for a successful amphibious invasion. But two things were

paramount -- control of the air and control of the sea. Supply

was necessary, trained ground troops were necessary,

reinforcement was necessary, and so on. But without

control of the air and sea, invasion was basically impossible.

A Hawker Hurricane with
British troops, 1940
Photo from Wikipedia

So while the German soldiers sang their song about moving

against England, the Luftwaffe (German air Force) and the

Kriegsmarine (German Navy) had to clear the way for

invasion.

The Battle of Britain

Hermann Goering (also spelled in German as Goring with

an umlaut on the “o”) was the head of the Luftwaffe, the

German air force. He had been a daring pilot in World

War I but was a braggart. He endlessly exaggerated his

importance and the ability of the Luftwaffe. Indeed, the

German air force had succeeded in Poland, Norway, the

Lowlands, and France, performing superbly as a tactical

support for German ground troops.

The Luftwaffe was a

key part of the Blitzkrieg -- which was an attack concentrated

at a key point by a breakthrough combination of air power,

tanks and armored vehicles, and artillery fire, followed by

infantry.

German HE 111s on a
bombing mission over England
Photo from Wikipedia  

The Luftwaffe had destroyed enemy planes in the air

and on the ground and wrecked enemy air bases.

But when Hitler and Goering began the Battle of Britain

on August 15, 1940, a battle fought totally in the air, it

was a different story.

The Spitfire, the superb fighter
plane of the RAF Fighter Command
Photo from Wikipedia 

Now the Germans, who did not possess a four engine,

long range bomber like the American B17 but only had

medium, two engine bombers, had to achieve air

superiority and even air supremacy in order for

Sealion to prevail.

German ME 109,
their best fighter plane in 1940
Photo from Wikipedia and
Bundesarchiv 

Air superiority is a military term meaning to have greater

air power than the enemy. Air supremacy is a higher

condition where one’s air power is effectively

unchallenged by the

enemy. The Germans should have gotten air supremacy before invading,

but air superiority was at the very least essential for invasion.

Stuka, Ju 87
Though useful early in the war, the
Stuka was an easy target for a Spitfire.
Photo from Wikipedia, German Federal Archive

On August 15, named Eagle Day by the Germans,

massive numbers of German bombers and fighters, about

1000 planes in all, flew against England. There had been

prior to this some limited German attacks on British

shipping in the English Channel, but now a giant air

Armada was launched directly against English soil.

Member of the Observer Corps
looks for approaching German planes
during the Battle of Britain, 1940
Photo from Wikipedia  

The targets were airfields, radar stations, and even

aircraft factories. But the real target was the Royal Air

Force (RAF) Fighter Command itself. Goering wanted to

destroy the RAF in one attack. But at the end of the day,

the Germans lost 75 air planes to 34 for the British.

Messerschmitt 110
Photo from Wikimedia Commons
and Bundesarchiv

The Germans outnumbered the British, but they could not

afford to lose such numbers. The Germans faced

several problems. First, their planes had to fly from

bases in occupied France across the Channel to

targets inside England. The RAF, however, was

already at the targets. The British planes could stay

in the air while the Germans, especially the fighter

planes, had to return to base for lack of fuel.

JU 88 Junkers
Phoro from Wikimedia Commons
and Deutsches Bundesarchiv

Secondly, the German bombers, being only medium

with two engines, had limited range and limited bomb

loads. They also had only a few

machine guns for protection.

Dornier DO 17
Photo from Wikimedia Commons 
and Deutsches Bundesarchiv

German planes were now no longer supporting ground

attacks as earlier in the war but were conducting

strategic bombing (attacking infrastructure --
airfields, radar and communication centers, etc),
something these planes were

not designed for.

The Stuka, the Heinkel HE 111,

the Dornier DO 17, the Junkers JU 88, and the
Messerschmitt ME 110, all good

bombers earlier in the war, now found themselves
beingmauled by the Hawker Hurricanes of the
RAF and especially by the outstanding British
fighter called the Spitfire.

The Germans had an excellent fighter plane called

the Messerschmitt 109 or ME 109, a.k.a. BF 109, but it

had limited range and air time because of the distance

to targets and fuel issues.

The Germans had the numbers, but the British had

the home field advantage and excellent fighter planes.

Nevertheless, had Goering and Hitler continued to bomb

the air fields and bases and aircraft factories, the

Germans might have reduced RAF Fighter Command

to the point of gaining German air superiority. They may

have also driven the British bases further away from the

coast, making them less able to deal with a cross

channel invasion.

Instead, because Churchill had Bomber Command

bomb Berlin, the Nazis retaliated by bombing London.

This was known as “the Blitz” of London. Although this

was destructive and terrifying, it was an extremely foolish

move militarily for the Germans. Not only did the Luftwaffe

lose planes, but now the British had time to rebuild and

repair air bases and airfields ... and even build new planes.

The RAF, at the start of the Battle of Britain, had about

700 airplanes. About 600 were fighter planes,

Hurricanes and Spitfires. The Germans had about 1400

bombers and 1300 fighter planes. By the end of

September 17 when Hitler indefinitely postponed Sealion,

the British had lost hundreds of fighter planes, and

the Germans had lost over 2000.

The inadequate German bombers and the strategic missions they

were not intended for, plus foolish decisions by Hitler

and Goering, such as bombing London by day,

and continuing bombing by night when daylight

raids proved too costly, plus outstanding efforts

by RAF Fighter Command, and a resolute Winston

Churchill resulted in a defeat for Germany in

the air Battle of Britain.

The German Navy -- consisting mainly of U-Boats

and a few surface ships and being no match for the

Royal Navy which had many destroyers, cruisers,

and battleships -- could not possibly protect an invasion

fleet using improvised barges as landing craft.

Could Sealion have Worked?

In 1974 the British Royal Military Academy at Sandhurst

conducted a wargame to test the feasibility of Sealion.

They concluded that with air power properly used,

with paratroops, and a screen of sea mines and the

best use of the Kriegsmarine and U-Boats, the Germans

could possibly land troops in Southeast England.

The Supermarine Spitfire,
with the Hurricane, it saved Britain in
1940 from possible invasion and defeat
Photo from Wikipedia 

But the Royal Navy would be powerful enough to

stop any second wave of landings and thereby cut

off the German supply line. German troops in England

would be without “beans, bullets, and bandages” -- no food,

ammunition, or medical supplies. As a result the Germans

would die or surrender on land. The Royal Navy would sink

German supply and troop ships at sea.

The result would be a German defeat.

A British destroyer during
World War 2
Photo from Wikipedia  

Had the Germans attained air supremacy, and been

trained as the Japanese had been to attack ships with aircraft,

had the German Navy laid mine fields at sea to protect

invasion sea lanes, had the U-Boats been able to hold off

the Royal Navy for awhile, had the weather been good for

German paratroops to land, had the Germans been able to

land tanks and armored vehicles, had the Germans been

able to resupply their army in the field in Southeast England

after the initial invasion, and had the Germans successfully
created a diversion to confuse and distract
the British, then maybe Sealion might

have succeeded.

But the odds were that Sealion would fail.

So, much like Napoleon had done a century before,

Hitler turned Eastward to attack Russia instead.

Sources and Further Reading:

The American Heritage Picture History of

World War II by C. L Sulzberger and American Heritage

Publishing, 1966; Wikipedia article on Operation

Sea Lion Wargame ;

and on Operation Sea Lion