Tag Archives: Sealion

Could there have been a German Invasion of Britain in 1940?

The Junkers Ju 87 Stuka. The primary close sup...
The Junkers Ju 87 Stuka. The primary close support weapon of the Luftwaffe in 1940. (Photo credit: Wikipedia)

Next week’s megagame Don’t Panic is an alternative history megagame about the German Invasion of Britain in 1940. It’s a popular what if and makes an interesting game for us British because the playing area is familiar to us from our everyday lives. At least it is familiar if you live in the South East. The megagame handbook has the village I live in centred in the combat example. German panzers occupy Redhill, the nearest town.

So could a German Invasion of Britain in 1940 have worked?

The answer is yes provided the Germans could have kept the Royal Navy and the RAF away from their invasion fleet and also managed to find enough suitable craft for moving an army across the channel. They also need to be able to sustain the landed army and reinforce it faster than the British can send reinforcements to fight them.

Personally I think that this is too much of a tall order for the Germans. They have no real appreciation of naval warfare. Nor do they have any joint planning staff. What allows the Allies to launch successful amphibious assaults later in the war is a combination of joint planning and lots of practice on a small scale before they tried bigger stuff. Even then Dieppe shows how hard it is to assault a lightly defended small port with armour.

The Kriegsmarine

English: Plan of battle of Operation Sealion, ...
English: Plan of battle of Operation Sealion, the cancelled German plan to invade England in 1940.  (Photo credit: Wikipedia)

The Kriegsmarine is smaller than the RN home fleet by an order of magnitude. Even if the German capital ships break into the Atlantic for commerce raiding the RN still has sufficient destroyer and lighter craft to wreak havoc in the channel.

The other major issue that the Kriegsmarine have is that they don’t have the tradition and corporate memory of the Royal Navy. So their skill level is confined to submarines and small to medium surface fighting vessels.

They’ve got no assault landing capability and no naval air. They also don’t have the same expansion capability the army had. So there isn’t the manpower available to them to suddenly crew loads of invasion barges. Those last need to be taken up from trade, which will have a negative impact on the German economy. So the Kriegsmarine doesn’t have the capacity to support a German invasion of Britiain in 1940.

The Luftwaffe

English: RAF Officer James Johnson, highest sc...
RAF Officer James Johnson, highest scoring Western Allies pilot against Luftwaffe.  (Photo credit: Wikipedia)

At best the Luftwaffe has parity with the RAF. However Britain is outbuilding the Germans in aircraft. As time passes the RAF grows in strength. Also lost RAF pilots tend to land in friendly territory and so get back in the air rapidly. Luftwaffe pilots tend to get lost in hostile space and become POWs.

The Luftwaffe is an asset in one way though. It exists to support the advance of the German Army. So if concentrated on that it can help the advance, however the liaison is in 1917 levels of planned support. It cannot be called off or amended once the planes are in the air. So only limited value in supporting a German invasion of Britiain in 1940.

That said, for the invasion to be successful the Luftwaffe needs air superiority over the invasion route and beaches. This is doable, but not guaranteed to be lasting.  It also needs to keep the RN at bay. I think the Luftwaffe vs RAF is the crucial battle. If the RAF win (and a draw counts as a win) then the Germans can’t invade Britain. If the Luftwaffe win then the Germans have a chance, but only a chance.

The Army

The German Army is good, experienced and tested in both Poland and the West. So it should outclass the British Army man for man on average.  The better British units will be better than the average Germans. The key issue though is numbers, and logistics. The British will have the best of both of these.

Conclusions

English: A relic from WW2 This gun emplacement...
English: A relic from WW2 This gun emplacement overlooks the flat beach of Pegwell Bay a possible landing area for the German invasion of Britain in the second world war. Further information can be found on this web site. http://www.kenthistoryforum.co.uk/index.php?topic=1049.0;prev_next=next#new (Photo credit: Wikipedia)

So if the Luftwaffe do an excellent job and keep the RAF and the Royal Navy at bay then the Kriegsmarine could put the German Army ashore. Once ashore the most likely outcome is that after hard fighting in the South East the Germans get defeated once additional British reinforcements arrive. The Germans will have a slower build up and their supply situation will be poorer than the British.

The hope for the Germans is for a collapse of civilian or political morale in the week after the German invasion.  Any more than a week and the entire British Army will be against them. British military successes are likely to restore faith.

This is where the megagame Don’t Panic will be exploring the what if of the German invasion. I’m really looking forward to it.

Operation Sealion: A Military Appreciation

Notice printed by the German police in advance...
Notice printed by the German police in advance of the invasion of Britain in WW2. Imperial War Museum, London. (Photo credit: Wikipedia)

The next megagame I’m going to is Don’t Panic a what if scenario on Operation Sealion, the planned German invasion of Britain in the autumn of 1940. I’m going to be the British Control. So no playing for me. However that doesn’t mean that I can’t look at how I would plan the Operation Sealion invasion myself.

Operation Sealion

Firstly we need to get into the nazi mindset. They’re essentially divide and conquer gamblers with no medium term view. They have an innate belief in their own superiority and on the inevitability of their eventual victory.

The other interesting thing is that the German General Staff see crossing the Channel as simply a large scale river crossing. To them it’s like crossing the Rhine, only a bit wider. This affects their thinking and probably explains why they didn’t ever attempt it. As they planned it, the obstacles just multiplied.

Fuhrer Directive 16

On 16th July 1940 Hitler issued Directive No. 16 On preparations for a landing operation against England. This set the initial conditions for planning Operation Sealion.

Since England, in spite of her hopeless military situation, shows no signs of being ready to come to an understanding, I have decided to prepare a landing operation against England and, if necessary, to carry it out.

The aim of this operation will be to eliminate the English homeland as a base for the prosecution of the war against Germany and, if necessary, to occupy it completely.

Situation

The German army has been victorious, sweeping all before it. All of continental Europe from Poland to the Pyrenees is under German control. Only Britain stands alone against Germany. The British army has been defeated in Europe and has left most of its first line equipment behind.

Invasion barges assembled at the German port o...
Invasion barges assembled at the German port of Wilhelmshaven (Photo credit: Wikipedia)

By mid August 1940 the panzer divisions will have been refitted, casualties either returned from hospital or been replaced. The luftwaffe is established in the French and Belgian airfields. The Kriegsmarine has assembled lots of barges ready for crossing the Channel.

In Britain the beach defences are being strengthened. However, the Briitsh Army is still short of transport and heavy equipment. The situation is so desperate that the British government has even called up old men and boys into a ‘Home Guard’. Weapons are so short that some of the Home Guard are armed with pikes.

Broadly the German invasion force can expect parity in numbers with the British in the invasion area. There is a qualitative advantage in terms of equipment and experience. The campaigns in Poland and the West have proved that beyond doubt. Operation Sealion is expected to follow the same pattern as the previous campaigns.

Mission

Hitler requires a speedy end to the war. German industry is short of manpower and the army needs to release skilled men soon. Operation Sealion is intended to bring the war to a speedy end.

Considerations for Operation Sealion

Broad vs Narrow Front

Normally military strategy suggests concentration of force. As an attacker you have a choice where you attack. A defender on the other hand has to spread out to cover all possible avenues of approach.

German preparations for operation Sealion, inv...
German preparations for operation Sealion, invasion of the british islands. A Panzer III tank modified for amphibious operations in France 1940. (Photo credit: Wikipedia)

The British can be expected to rapidly deploy their remaining mobile reserve, including an armoured division, against any landing. This could tip the balance before strong enough German forces are ashore. The speed of response is likely to be slower if they cannot be sure where our schwerpunkt is located. Multiple landing points will aid this.

Ports

We need to capture a port as early as possible to enable unloading panzer forces. Once panzers are set free in England we can be assured of victory.

Both of these point to a strategy of attacking multiple small ports to ensure that at least one is captured rapidly.

Airfields

We also need forward airfields to help the Luftwaffe support ground forces. It will also enable air landing troops to be brought in. This will speed up the force build up and make it harder for the British to defeat us in detail before we can join up.

This leads to the selection of ports. RAF bases at Marston and Tangmere have recently been abandoned and are in close proximity to ports. Similarly Dover has two airfields in close proximity and the castle is a major threat to our use of the channel.

Causing Civilian Panic

English: Home Guard soldiers training with a '...
English: Home Guard soldiers training with a ‘Blacker Bombard’ spigot mortar No. 3 GHQ Home Guard School, Onibury near Craven Arms, Shropshire (Photo credit: Wikipedia)

Fleeing civilians are useful to the German success. They cause bottlenecks that stop the enemy bringing up reinforcements. They also adversely affect morale. This latter is important politically as well as militarily. We need the British Government to sue for peace. The faster this happens the better.

Effective ways of reducing civilian morale are:

  • airborne troops behind the main lines (even if only rumoured);
  • tank breakthroughs, especially if accompanied with pictures at iconic places for the newspapers and cinema news reels;
  • sinking of supply ships so that rationing is tightened;
  • terror bombing of cities, especially London and other industrial centres.

Conclusion

Operation Sealion requires a rapid buildup with simultaneous action at sea and in the air to split or slow the British response is required to give time for a foothold to be established in England. This will maximise political pressure and ensure military victory.

General Outline

Operation Sealion’s broad strategic goals must be to get a foothold, rapidly expand it and encourage the political opposition in the UK. Ways to do this are

  • surge the Kriegsmarine into the Atlantic for commerce raiding (apart from the bits directly needed for supporting the invasion)
  • use a u-boat screen to stop the RN getting in amongst the invasion fleet.
  • select four small ports across the Kent and Sussex coast for direct seaborne assault supported from the air. Put a battalion of paras on the closest airfield to the selected beaches
  • reinforce success with air landed troops on the captured airfields and tanks into the captured ports
  • transfer luftwaffe units to the captured airfields as rapidly as possible to increase loiter time and range
  • collect up the paras as soon as possible for a second drop on London or wherever intelligence suggests Churchill or the Royal Family are hiding out.