Operation Sealion (Unternehmen Seelöwe)

[Theobald]

Operation Sealion (Unternehmen Seelöwe)

Immediately after the defeat of France in June 1940, Adolf Hitler ordered his generals to organize the invasion of Britain. The invasion plan was given the code name Operation Sealion. The objective was to land 160,000 German soldiers along a forty-mile coastal stretch of south-east England.

Within a few weeks the Germans had assembled a large armada of vessels, including 2,000 barges in German, Belgian and French harbours. However, Hitler's generals were very worried about the damage that the Royal Air Force could inflict on the German Army during the invasion. Hitler therefore agreed to their request that the invasion should be postponed until the British airforce had been destroyed.

On the 12th August the German airforce began its mass bomber attacks on British radar stations, aircraft factories and fighter airfields. During these raids radar stations and airfields were badly damaged and twenty-two RAF planes were destroyed. This attack was followed by daily raids on Britain. This was the beginning of what became known as the Battle of Britain.

Although plans for an invasion of Britain were drawn up Adolf Hitler was never very enthusiastic about them and they were eventually abandoned on October 12, 1940. Instead, Hitler attempted to batter Britain into submission by organising a sustained night-bombing campaign.



The projected invasion on Britain included:

• Army Group A (6 divisions) invading Kent via the areas near Ramsgate, Folkstone and Bexhill
• Army Group B (4 divisions) invading Sussex and Hampshire via the area around Brighton and the Isle of Wight.
• Army Group C (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.

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

[Theobald]

DIRECTIVE No. 16 : Operation Seelöwe (Sealion)

16 July 1940

Concerning preparations for an amphibious operation against England.

Since Britain still shows no sign of willingness to come to an agreement in spite of her hopeless military situation, I have decided to prepare and if necessary carry out an amphibious operation against England.

The purpose of this operation will be to eliminate the English mother country as a base for continuation of the war against Germany and, if it should become necessary, to occupy the entire island.

To this end I order as follows:

1. The amphibious operation must be carried out as a surprise crossing on a broad front extending approximately from Ramsgate to the region of the Isle of Wight, with Luftwaffe elements assuming the role of artillery, and naval units assuming the role of engineers.
Each individual branch of the Wehrmacht will examine from its own viewpoint whether it appears practicable to carry out subsidiary operations, for example to occupy the Isle of Wight or Cornwall County, prior to the general crossing, and will report its findings to me. I reserve the decision to myself.

Preparations for the overall operations must be completed by mid-August.

2. These preparations will include the creation of conditions which will make a landing in England possible:
a) The English air force must be so far neutralized, both actually and in morale, that it will offer no appreciable resistance to the German crossing operation;
b) Lanes must be cleared of mines;
c) Both outlets of the Straits of Dover, and the west entrance to the English Channel in a line approximately from Alderney to Portland, must be sealed off by a dense belt of mines;
d) The coastal areas must be commanded and covered by the fire of heavy coastal artillery;
e) It is desirable that all British naval forces should be tied down in action, both in the North Sea and in the Mediterranean - here by the Italians - shortly before the crossing; efforts must be made now already by means of air and torpedo attacks to weaken as far as possible the British naval forces presently in those waters.

3. Organization of Command and Preparations.
Under my command and in accordance with my general directives the commanders in chief of the three branches of the Wehrmacht will direct the operations of their forces employed in the operation.
From 1 August on, the operations staffs of the commanders in chief of the Army, the Navy, and the Luftwaffe must be within the area with a maximum radius of 30 miles from my headquarters at Ziegenberg.
To me it appears advisable for the most vital elements of the operations staffs of the commanders in chief of the Army and the Navy to occupy mutual premises in Giessen.
The commander in chief of the Army will thus have to establish an army group headquarters to conduct the operations of the landing armies.

The operation will be given the designation Sea Lion (Seelöwe).
During preparations and in the execution of the operation the missions of the three branches of the Wehrmacht will be as follows:
a) Army. Preparation of plans of operations and of a crossing plan initially for all units to be shipped in the first wave. The units accompanying the first wave will remain under Army control (under the individual landing groupments) until it is possible to subdivide their mission into responsibility for (1) support and protection for the ground forces, (2) protection of the ports of debarkation, and (3) protection for the air bases to be occupied.
The Army will also allocate shipping space to the individual landing groupments and will define the points of embarkation and debarkation in agreement with the Navy.

b) Navy. Procurement and assembly of the required shipping space at the points of embarkation designated by the Army and in accordance with nautical requirements. As far as possible use will be made of ships from defeated hostile countries.
The necessary naval advisory staff, escort ships, and other protective naval units will be provided by the Navy at each crossing area.In addition to the protection afforded by the air units employed, naval forces will protect the flanks of the entire movement across the Channel. Orders will be issued regulating the chain of command during the actual crossing.

Another mission of the Navy is to direct the uniform disposition of coastal artillery, namely, of all naval and Army batteries which can be used against naval targets and to generally organize the control of fire.The largest possible number of the heaviest artillery units will be so placed that they can be brought into effective action as speedily as possible to protect the flanks of the movements against hostile naval attack. For this purpose all railway artillery, reinforced by all available captured guns but minus the K-5 and K-12 batteries earmarked for counterbattery fire against shore-based hostile artillery in England, will be withdrawn from present positions and emplaced on railway turntable mounts.

In addition to the above, all platform guns of the heaviest types will be so emplaced under concrete protection opposite the Straits of Dover that they will be proof against even the heaviest air attacks. They will be so sited that they will command the Straits under all circumstances as far as their ranges permit.The technical work involved will be carried out by Organization Todt.

c) Luftwaffe. The mission of the Luftwaffe will be to prevent interference by hostile air forces. In addition airpower will be employed to neutralize coastal fortifications which could deliver fire in the landing areas, to break the initial resistance offered by the hostile ground forces, and to destroy reserves during their forward movement. These missions will require extremely close contact between the individual air units and the landing forces of the Army.

It will also be important for air units to destroy roads which could be used by the enemy to move reserves forward, and to attack naval units approaching the areas of operations while still far distant from the crossing routes.I request recommendations on the use of paratrooper and glider and other airborne forces. The question must be examined together with the Army whether it would be wise to withhold paratrooper and other airborne forces during the initial stages as a reserve force which could be moved quickly to critical areas in the event of an emergency.The Wehrmacht chief signal officer will ensure that all necessary preparations are made to establish communications between France and England.Preparations will be made in cooperation with the Navy to lay what is still available of the 48 miles of marine cable taken up from the East Prussian canal.

4. Preparations to ensure the necessary communications between France and the English mainland will be
handled by the chief of the armed forces signals

5. I request the commanders in chief to submit to me as early as possible:

a) The measures planned by the Navy and the Luftwaffe to create the conditions necessary for the Channel crossing operation (Item 2, above);
b) Details on the disposition of the coastal artillery batteries (Navy);
c) A survey of the shipping to be employed and of the methods of concentration and equipment. All civilian agencies participate? (Navy);
d) Plans for the organization of air defense in the areas of concentration for troops and for equipment to be used in the crossing operation (Luftwaffe);
e) Channel-crossing schedule and plan of operations of the Army, and organization and equipment of the first attack wave;
f) Organization and action planned by the Navy and the Luftwaffe for the defense of the crossing movement itself, for reconnaissance, and for support during the landing;
g) Recommendations concerning the commitment of paratrooper and other airborne forces and concerning the command of forces after an adequately large area has been brought under control in England (Luftwaffe);
h) Recommendations for the location of headquarters for the command echelons of the commander in chief of the Army and the commander in chief of the Navy;
i) Comments by the Army, the Navy, and the Luftwaffe as to whether and what partial operations are considered practicable prior to the general amphibious operation;
k) Recommendations by, the Army and the Navy concerning the chain of command during the crossing, while seaborne.

[Hand-initialed]
J[odl]
K[eitel]
(signed)
Adolf Hitler
Distribution:
Commander in Chief,
Commander in Chief,
Commander in Chief,
Wehrmacht Operations,
National Defense Branch

Army Ribbon Copy
Navy Second Copy
Luftwaffe Third Copy
Office Fourth Copy
Fifth to Seventh Copies

[Theobald]

Some links :

1/http://www.flin.demon.co.uk/althist/seal1.htm

Why Sealion was not an option for Hitler to win the war

One of the more common suggestions that crop up at all-too regular intervals goes along the lines of: "If Hitler hadn't switched from bombing airfields to bombing cities, then Operation Sealion would have worked."
Unfortunately for these suggestions, the plan for Sealion was perhaps the most flawed plan in the history of modern warfare. Getting it to a workable state requires so many changes that an author's artistic license would be revoked.
What follows is an analysis of Sealion in OTL.

2/http://www.spartacus.schoolnet.co.uk/2WWsealoin.htm

Some quotes

3/http://www.alternatehistory.com/gate...s/Sealion.html

Why Operation Sealion wouldn't work

[Theobald]

Other links (in German) :

http://www.dhm.de/lemo/html/wk2/kriegsverlauf/seeloewe/

http://www.dhm.de/lemo/forum/kollekt...323/index.html