Operation Sealion fails

The British lose the Battle of Britain and the Kriegsmarine is barely able to transport 67,000 soldiers across the English Channel in towed river boats to Southern England, only for the invasion force to immediately get bogged down south of Cambridge. There are no supply lines, due to the Royal Navy swarming around the channel, forcing the Germans to resort to looting and pillaging the locals to support themselves.

However, after a period of time, the Germans decide to surrender to the superior British military, thereby rendering Operation Sealion a utter failure.

What impact does this military catastrophe have on World War II?
 
So one problem here is that item 1 (losing the Battle of Britain) and item 2 (Royal Navy swarming the channel) don't mix. Namely, if the Battle of Britain is truly lost lost (rather than a temporary window), then the Navy's going to be prevented from doing anything in the English Channel.

However, let's say that the BoB is lost and the RAF won't be replenished enough to regain at least air parity if not superiority, but you've got a bunch of Germans marooned on the Island. That becomes 67,000 (less the corpses) PoWs rather quickly. A de-supplied invasion is a dead invasion.
 
This comes up often enough that, as you may have noticed, there's a pinned compendium of Sea Lion threads at the top of the threads page. So I will be brief.

First, the comparatively small number of infantry involved means Germany isn't dealt a crushing blow in material terms there, although the probable loss of specialized units like paratroopers has to be accounted for.

Second, what remains of the German surface fleet presumably ceases to exist at the end of this exercise. It wasn't going to turn the war at any other moment, but now that it's gone, that frees up more of the RN that was on home defense duty to wander off doing other things, namely hunting submarines in the Atlantic, reinforcing the Mediterranean and Far East, etc., etc.

Third, if the fallout is bad enough, especially in political terms, it's possible this shakes the Nazis into reconsidering Barbarossa the following year, but I'm less sure there. That's a maybe. In Nazi psychology the unfortunate war of rivalry with Britain and the preferred war of conquest with Russia really were separate things.
 
I'd note that landing a force of 67K lightly-equipped and not resupplied troops on the south coast is not going to get bogged down "south of Cambridge", unless you mean so far south of Cambridge to be near the South Downs. If the Germans are reduced to looting and pillaging for supplies, they're going to be scattered. "After a period of time" is going to be 10 days, tops. The comparison with Arnhem might be instructive. Here, a roughly similar number of troops (40K) were dropped in Market, with comparable levels of equipment and supplies. They landed in areas that welcomed them as liberators, making basic food gathering somewhat easier. In the Sealion case, there is no Garden. Arnhem held out for around 10 days, and that's got to be your rough baseline.

As you will have noticed, Sealion has a long history here. It's been a topic of discussion for longer than this website has existed, and has been extensively debated for over 20 years to my certain knowledge.

Namely, if the Battle of Britain is truly lost lost (rather than a temporary window), then the Navy's going to be prevented from doing anything in the English Channel.

However, German maritime assets are going to be in the Channel at night. The speed of the assets ensures that. At night, there's very little the Luftwaffe can do to stop RN light forces.
 
What I'm interested in that I haven't seen discussed in most Sealion threads is that the British intended to use mustard gas en masse on the beaches. If this spurred Hitler into using chemical weapons en masse as well, then we get an extremely different Eastern Front - with mass use of chemical warfare greatly impeding German advances [from destruction of horse-driven transport.]
 
I'd note that landing a force of 67K lightly-equipped and not resupplied troops on the south coast is not going to get bogged down "south of Cambridge", unless you mean so far south of Cambridge to be near the South Downs. If the Germans are reduced to looting and pillaging for supplies, they're going to be scattered. "After a period of time" is going to be 10 days, tops. The comparison with Arnhem might be instructive. Here, a roughly similar number of troops (40K) were dropped in Market, with comparable levels of equipment and supplies. They landed in areas that welcomed them as liberators, making basic food gathering somewhat easier. In the Sealion case, there is no Garden. Arnhem held out for around 10 days, and that's got to be your rough baseline.

As you will have noticed, Sealion has a long history here. It's been a topic of discussion for longer than this website has existed, and has been extensively debated for over 20 years to my certain knowledge.



However, German maritime assets are going to be in the Channel at night. The speed of the assets ensures that. At night, there's very little the Luftwaffe can do to stop RN light forces.
As I understand it, the premise of this thread, a la the Sandhurst war game, is that the Germans land their invasion force -- with magic pixie dust, perhaps -- and then fail to reinforce and resupply it.

It should be noted for the original poster's benefit that in the history of Sea Lion threads here there is strong skepticism of that scenario. To the contrary, it is generally believed that the German invasion flotilla would be unable to achieve strategic surprise and would therefore probably be ambushed by the RN on its first trip across, very likely with catastrophic losses.

Hence in part David Flin's point here that whatever force lands is likely to already be disorganized, scattered, and low on supplies, and to grow rapidly more so as time goes by.

Edit: And also, lest there be any doubt we are challenging Sandhurst on this, that was a precondition of their simulation, not an outcome. Everybody involved recognized that if the Royal Navy moved in force against the first wave of the invasion flotilla, there would be no point continuing the exercise.
 
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What I'm interested in that I haven't seen discussed in most Sealion threads is that the British intended to use mustard gas en masse on the beaches. If this spurred Hitler into using chemical weapons en masse as well, then we get an extremely different Eastern Front - with mass use of chemical warfare greatly impeding German advances [from destruction of horse-driven transport.]

This actually did come up in a recent thread. I'll see if I can find the link. There was some question about whether the British actually had the plans and orders in place to use gas (I was on the skeptical side but it was a legitimate uncertainty).

If it does indeed release all sides to use chemical warfare, though, the effects would almost certainly be catastrophic, not just for the eastern front but also use against cities.
 
If it does indeed release all sides to use chemical warfare, though, the effects would almost certainly be catastrophic, not just for the eastern front but also use against cities.
The international political fallout, particularly in the US of Britain being the first to use Chemical weapons would be the Chinese version of interesting, though. Might this kill Lend-And-Lease?
 

SsgtC

Banned
The international political fallout, particularly in the US of Britain being the first to use Chemical weapons would be the Chinese version of interesting, though. Might this kill Lend-And-Lease?
No. The British would be using it to stop an invasion, not to launch an attack. That's a huge difference. The only way Lend-Lease gets canned is if the Brits used chemical weapons in an OFFENSIVE first strike. Not if they're used in a defensive role to stop an invasion.
 
The British lose the Battle of Britain and the Kriegsmarine is barely able to transport 67,000 soldiers across the English Channel in towed river boats to Southern England, only for the invasion force to immediately get bogged down south of Cambridge. There are no supply lines, due to the Royal Navy swarming around the channel, forcing the Germans to resort to looting and pillaging the locals to support themselves.

However, after a period of time, the Germans decide to surrender to the superior British military, thereby rendering Operation Sealion a utter failure.

What impact does this military catastrophe have on World War II?

South of Cambridge you say? Do you know where Cambridge is? It would require that 67,000 troops - which is about a Corps / 3-4 divisions worth of troops with zero logistics have in the face of a million armed men (including about 27 Army divisions) with all the advantages of internal transport and robust logistics, artillery and tanks, have captured about 1/4 of England. Including London - which is in the way

Given the realitiy of the situation they are unlikely to get further than South of Dover and more probably remain south of Calais.
 

SsgtC

Banned
South of Cambridge you say? Do you know where Cambridge is? It would require that 67,000 troops - which is about a Corps / 3-4 divisions worth of troops with zero logistics have in the face of a million armed men (including about 27 Army divisions) with all the advantages of internal transport and robust logistics, artillery and tanks, have captured about 1/4 of England. Including London - which is in the way

Given the realitiy of the situation they are unlikely to get further than South of Dover and more probably remain south of Calais.

Except you're forgetting that all Germans are Super Soldiers. Each one capable of taking on an entire platoon all by himself! No Army could possibly hope to stop them.
 
I've always argued that a successful repulse of Sealion, whether sunk in the channel or strangled on the beaches, is that Lend-Lease will be a dead letter. The simple argument against it will be 'Britain beat 'em. They don't need our help.'

This has considerable consequences on the Eastern Front, where lend Lease was almost thr entire logistical train of the red Army (Dodge Trucks, Jeeps, over 900 locomotives, 30000 boxcars and other rolling stock, thousands of miles of rails, and half a pound of food per soldier per day. Thats going to slow the red army down in its advances from Operation Uranus onward.
 
Except you're forgetting that all Germans are Super Soldiers. Each one capable of taking on an entire platoon all by himself! No Army could possibly hope to stop them.
I took the slightly charitable view that the poster meant Canterbury rather than Cambridge.
Easily confused, unless your English or have a map.

By the way, one of daughters lives in Canterbury, and my elder son is at uni in Cambridge.
Both about 90 minutes drive, but in opposite directions - Canterbury south, Cambridge north.
 
I took the slightly charitable view that the poster meant Canterbury rather than Cambridge.

Funnily enough, earlier this evening I left youtube on autoplay in the background while I was doing something else and this video came up. I wouldn't mention it but for a clear reference to the German invasion not planning to go any further north than just south of Cambridge. Maybe the OP watched this first?

 
I've always argued that a successful repulse of Sealion, whether sunk in the channel or strangled on the beaches, is that Lend-Lease will be a dead letter. The simple argument against it will be 'Britain beat 'em. They don't need our help.'

This has considerable consequences on the Eastern Front, where lend Lease was almost thr entire logistical train of the red Army (Dodge Trucks, Jeeps, over 900 locomotives, 30000 boxcars and other rolling stock, thousands of miles of rails, and half a pound of food per soldier per day. Thats going to slow the red army down in its advances from Operation Uranus onward.

But it's just as likely to lead to the opposite effect as those who assumed Britain was finished regardless see the German war machine isn't all conquering.

This actually did come up in a recent thread. I'll see if I can find the link. There was some question about whether the British actually had the plans and orders in place to use gas (I was on the skeptical side but it was a legitimate uncertainty).

Faced with 67,000 troops stuck in a beachhead, lacking supplies I doubt the British are going to break out the Mustard gas.

Overall as others have pointed out this is an impossible scenario, the only way any Germans get ashore is if they manage to swim to the beaches from a sinking barge.
 
Except you're forgetting that all Germans are Super Soldiers. Each one capable of taking on an entire platoon all by himself! No Army could possibly hope to stop them.

And you sir have obviously forgotten what they are up against...

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"THEY DON'T LIKE IT UP THEM SIR, THEY DON'T LIKE IT"
 
As I've said in some of these threads when it's come up, from what I've read the understanding between Ireland and the UK at Governmental level was that any Sealion invasion would mean that Ireland would enter the war (primarily as the threat couldn't be ignored at that stage), so if that happens you've automatically improved the situation in the Atlantic for the remainder of the war (I think the RN studies suggested a reduction of 10% of losses at least if the Treaty Ports were in use), potentially extra manpower, balanced with having to make extra resources to Ireland (AA guns, fighters, radar systems).
 
I've always argued that a successful repulse of Sealion, whether sunk in the channel or strangled on the beaches, is that Lend-Lease will be a dead letter. The simple argument against it will be 'Britain beat 'em. They don't need our help.'

This has considerable consequences on the Eastern Front, where lend Lease was almost thr entire logistical train of the red Army (Dodge Trucks, Jeeps, over 900 locomotives, 30000 boxcars and other rolling stock, thousands of miles of rails, and half a pound of food per soldier per day. Thats going to slow the red army down in its advances from Operation Uranus onward.

I don't agree mate

Actions like the destruction of the French fleet and supporting the Greeks* as much as possible for example - were received 'positively' in the US as they proved to the US GOV that the UK was serious about this whole standing up to the Nazi's thing - and so beating the snot out of a German invasion would be positively received - after all no point sending loads of military equipment to the Brits if they are only going to throw in the towel and this equipment might eventually end up opposing US Forces somewhere in the future!

*In fact the only reason I (which is big of me) forgive Winston for forcing Wavell to carry out this 'forlorn hope' of an op when his army was already massively overstretched!
 
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