What is needed for a successful Napoleonic conquest of Britain?

Before 1900 forum has a Sealion, my life is complete
Yes and like sealion any POD that makes it possible is so far in the past that it is no longer the same operation, the invaders are not the same people and the defenders are not really the same country.
 
Yes and like sealion any POD that makes it possible is so far in the past that it is no longer the same operation, the invaders are not the same people and the defenders are not really the same country.

Well I think the difference is you can have PODs that are small enough that Boney is still Boney but it is still very safely an awful lot of work and a long process to get him there on the Kentish shore and even once there it could still all go very wrong for him.
 

Saphroneth

Banned
Well I think the difference is you can have PODs that are small enough that Boney is still Boney but it is still very safely an awful lot of work and a long process to get him there on the Kentish shore and even once there it could still all go very wrong for him.
Among the examples of things that could cause a problem are actually the same defences as would cause a problem with Sealion! This is more because Sealion is so logistically challenging than anything.
 
France already tried to invade Britain via Ireland in OTL - the 1798 Irish rebellion was supported with French troops landing in Mayo. They defeated the British at Castlebar, but were eventually destroyed. A second "wave" of troops tried to land in Donegal but never reached the beachs after the Royal Navy intervened.
 

Saphroneth

Banned
There's also the rather farcical invasion that landed at Fishguard. My favourite detail about that is that local women walked around a hill in a circle wearing red cloaks, so the French saw an endless stream of "redcoat" reinforcements arriving!
 
There's also the rather farcical invasion that landed at Fishguard. My favourite detail about that is that local women walked around a hill in a circle wearing red cloaks, so the French saw an endless stream of "redcoat" reinforcements arriving!
To be fair to them, traditional Welsh dress with a red shawl & tall black hat could well (at a distance & to scared troops) look like a bunch of British Infantry.
 

Saphroneth

Banned
To be fair to them, traditional Welsh dress with a red shawl & tall black hat could well (at a distance & to scared troops) look like a bunch of British Infantry.
Yes, that's exactly what happened. It's just rather amusing nevertheless - much like the way that a sentry from one British regiment once shot a wheel of cheese and the entire regiment never lived it down.
 
I think the British have always been hyper-critical when it comes to their own equipment. The notorious 'Forty Thieves' were a class of 74's which were supposedly slow and clumsy, yet one of them came within an ace of capturing one of the (allegedly) very fast American ship-sloops, and the American ship only got away by throwing its guns and most of its stores overboard.
 

Saphroneth

Banned
I think the British have always been hyper-critical when it comes to their own equipment.
Really, I think everyone is - it's just that in the British case the historians were too!
:p

Or, rather, the historians were more prone to record the gripes. But yes, it often seems like the way it works is that if you lose then it's the fault of the equipment, and if you win it's your skill! (The British had more actions than anyone else, and more to the point more actions where the participant got home to talk about them - so both effects show up more.)

An example of this kind of thing later in the century is in the Armstrong guns of the late 1850s and early 1860s, which (AFAICT) were about as reliable as the Krupp guns of a decade later - but the British felt that wasn't good enough and just ditched them!
 
Replace British beer with French beer, the British will collapse In a week and beg for mercy by having to drink French beer. :)

The one thing the United Kingdom has made damn sure of is no one was going one up them with a navy.

So either France gets a much bigger navy, or it's a crapshoot.

They don't have to land in London, if they could manage some form of a beach head elsewhere and pray they can keep the Royal Navy off its back long enough to resupply them, they could stand a chance. Slim mind you, but a chance none the less. I would say it would be easier in 1811-1812 than at other dates in the future.

Again the French will have to invest heavily in its navy
 
You will need the Spanish Navy involved in any invasion to make it work, like with French kings knew before the revolution the Spanish navy was necessary for any effective attack on Great Britain. People like to denigrated the Spanish fleets competency, but like the French navy it was a shortage of trained personal that hurt it the most. But ship for ship the Spanish ships of the line were as good as any in the Royal Navy and the Royal Navy did admit that fact.
 

Saphroneth

Banned
You will need the Spanish Navy involved in any invasion to make it work, like with French kings knew before the revolution the Spanish navy was necessary for any effective attack on Great Britain. People like to denigrated the Spanish fleets competency, but like the French navy it was a shortage of trained personal that hurt it the most. But ship for ship the Spanish ships of the line were as good as any in the Royal Navy and the Royal Navy did admit that fact.
Necessary but not sufficient, I think. The RN was larger than the French, Spanish and Dutch fleets combined.
DURING THE REVOLUTIONARY and Napoleonic wars the Royal Navy achieved the most overwhelming series of victories in the history of naval warfare. The main fleets of France, Spain, Denmark and The Netherlands were captured or destroyed – in some cases more than once – and there were innumerable successes in single-ship actions. After Trafalgar, the British battlefleet was not seriously challenged.

Brown , David K. Before the Ironclad: Warship Design and Development 1815-1860 (Kindle Locations 219-222). Seaforth Publishing. Kindle Edition.

Speaking specifically of Spain, the Spanish lost 17 liners and 16 frigates to capture at sea, two liners and three frigates sunk at sea, and lost four liners and three frigates in port (destroyed and captured combined).

Speaking of ships in general, the enemy lost a total of 149 liners and 208 frigates to British action, and the British lost five liners and sixteen frigates to enemy action.
The British also lost 26 liners and 62 frigates to accident of various kinds, while the French lost 32 rated ships total to accidental losses and the Netherlands two. (Given relative time at sea, this is really quite impressive for the British.)
 
True the British Navy was the largest but it was committed to operations across the world. The French wanted to concentrate superior force of Ship of the Lines in the Channel to allow Napoleon time enough to make it across the channel. So using both the French and Spanish fleets that were based in Europe they were attempting to do just that and they did give the Royal Navy a good cause to worry. Whether it would work well in OTL it did not but don't lightly dismiss it the Admiralty certainly did not. Also this is before Trafalgar.
 
True the British Navy was the largest but it was committed to operations across the world. The French wanted to concentrate superior force of Ship of the Lines in the Channel to allow Napoleon time enough to make it across the channel. So using both the French and Spanish fleets that were based in Europe they were attempting to do just that and they did give the Royal Navy a good cause to worry. Whether it would work well in OTL it did not but don't lightly dismiss it the Admiralty certainly did not. Also this is before Trafalgar.

The problem is that Napoleon needed rather more time than he suspected. There are certainly shades of Sea Lion to the plan Bonaparte came up with OTL even down to having a training exercise in which thirty of the intended troop transports were wrecked with heavy loss of life. Lord Keith in charge of the naval portion of the defence had some 218 warships under command though of course these were not all battleships (I think there were about 70 RN battleships in home waters).


For land forces there were in 1805 some 70,000 regulars stationed in Britain with another 35,000 in Ireland. There were perhaps another 100,000 militia and yeomanry troops. Also recall these had the advantage of strong fortifications.
 
True the British Navy was the largest but it was committed to operations across the world. The French wanted to concentrate superior force of Ship of the Lines in the Channel to allow Napoleon time enough to make it across the channel. So using both the French and Spanish fleets that were based in Europe they were attempting to do just that and they did give the Royal Navy a good cause to worry. Whether it would work well in OTL it did not but don't lightly dismiss it the Admiralty certainly did not. Also this is before Trafalgar.

And if they had evaded Nelson they would still have faced a superior fleet at the entrance to the channel. it moved there on the initiative of the squadron admirals as the situation developed.

The possible opponents had several disadvantages, superior training, superior officer corps, superior artillery, better ships much much better geography and following the american war a superior tactical system.

To give the two normally quoted faster ships.


The mentions of faster French ships come from British service. A sailing ship gets speed from things. The hull form and the rig. The french ships are only consistenly faster with a British rig which goes to method and crew/captain training.

The goepraphy is appalling. Just about the only circumstance in which in a french fleet can get to the channel requires either evading the Med Fleet or a series of gales that put the the RN into Torbay, ad the french scattered across the atlantic.
 

Saphroneth

Banned
True the British Navy was the largest but it was committed to operations across the world. The French wanted to concentrate superior force of Ship of the Lines in the Channel to allow Napoleon time enough to make it across the channel. So using both the French and Spanish fleets that were based in Europe they were attempting to do just that and they did give the Royal Navy a good cause to worry. Whether it would work well in OTL it did not but don't lightly dismiss it the Admiralty certainly did not. Also this is before Trafalgar.
They didn't dismiss it, but they did feel they could handle it. Hence the famous quote:

"I do not say they cannot come. I only say they cannot come by sea."
 

ben0628

Banned
Well I think its time we start thinking outside the box. First, a couple of facts.

1) A its narrowest point, the English Channel is 19 miles wide and about 150 feet deep.
2) A cubic foot of hard soil weighs about 80 pounds.

So if the French army was to build a 19 mile land bridge across the the English channel that was 150 deep and 40 feet wide (wide enough for wagons going both ways and the occasional redoubt with artillery to fight the British Navy), it would take 601,920,000 cubic feet of soil, which weighs approximately 24,076,800 tons.

If the French army deploys a work force of 50,000 people and all the soil necessary is readily available and each laborer can carry 1 ton of soil a day, that means it would take the French 481 days to build the land bridge.

So if the French really, REALLY want to invade England, it would take them about 1.3 years to achieve victory (and that's without a navy).

If we use math, ANYTHING is possible.

If this was actually realistically possible, I could see the horror in England as the French juggernaut slowly inches forward across the channel. It would feel like a modern example of Alexander's siege of Tyre.
 
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or what if Napoleon went all in on steam powered warships? What if the French navy had their own equivalent to Napoleon?
 
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