British invasion of Denmark at start of WW1

[Alex1guy]

Perhaps they could use the Frisian Islands as a jumping off point to invade Germany itself.

Ah an old guard I see haha

 

[VoidStalker]

I kinda want to see a TL set on a British invasion using the BEF at the start of WWI in the can't look away from a train wreck sort of thing. That and the fallout when it fails. Though to me it would take a non military types to push such a thing through.

 

[ArtosStark]

Ah an old guard I see haha

Weirdly, Borkum is technically part of the Frisian islands. And it was considered important for plans that could, maybe, possibly, see some level of invasion of Germany. Though the plan was never to launch from there. So..... Sort of?

 

[Alex1guy]

Weirdly, Borkum is technically part of the Frisian islands. And it was considered important for plans that could, maybe, possibly, see some level of invasion of Germany. Though the plan was never to launch from there. So..... Sort of?

Oh I was pointing out a referencing an ancient alt.hist meme from like 10 years ago, it was an epic 80 page debate on an alternate d day invasion which involved invading Germany from the Frisian islands. Old lore now haha

 

[ArtosStark]

Oh I was pointing out a referencing an ancient alt.hist meme from like 10 years ago, it was an epic 80 page debate on an alternate d day invasion which involved invading Germany from the Frisian islands. Old lore now haha

I know. When I first joined I saw references to it. So I tracked it down and read it. Or most of it. It got kind of repetitive after a while. Nice decent into madness....

 

[McPherson]

That kind of falls in the same category as the submarine though, Zeppelin's first prototype had only got airborne in 1900 and he immediately had to liquidate the company. LZ2 only flew in 1906 (and only once, as its engines were both damaged). The first truly successful Zeppelin from a military standpoint was LZ4 in 1908. So the plans in 1905 wouldn't really have included them. Once their use was demonstrated the British were very interested, but would, like with submarines, have to wait for sufficient numbers of fully capable machines. Even if Mayfly had not collapsed or the program continued thereafter, they would probably not quite have reached that point in 1914. And independent scouting missions would likely have to wait until the GF had sufficient zeppelin cover, delaying it still more.

Hence; look at Mister Glenn Curtiss.

Delay might be a better description then deny. AIUI mines, particularly WW1 mines, can be laid in ways that make it harder to clear them but I am not sure you can make them unclearable with WW1 technology, as long as the ones clearing have control of the area.

This depends on the type of offensive mine field laid. Hertz mines are easy. Some kind of failsafe idiot proof mechanical actuated anti-clearing charges (as sweep snares) would have to be dispersed among the ship-killers to make paravane sweeping difficult. And of course the mines have to be refreshed periodically. Raiding would be the operant condition rather than stand sentry on the fields. The closer into the shallows, the better.

 

[ArtosStark]

Hence; look at Mister Glenn Curtiss.

Its still too early. In 1905 Glenn Curtis was a pioneer in Motorcycles, not aircraft. The most he had done with aircraft was supply an engine for Tom Baldwin's work. It was only in 1907 that Curtiss would be invited to join Alexander Graham Bell to join the Aerial Experiment Association, mostly on the strength of his engine work. It would be 1908 before he would make any public splash as an aviator and 1909 before his first production aircraft flew. By that time, his accomplishments would come along with the Wrights, and those of Bleriot. And by that time the British had work going on at the Royal Balloon Factory by both Cody and Dunne (with Dunne unfortunately being much preferred by his superiors).

On the naval side, Curtis's involvement in the first take off from a ship was certainly paid attention to and led to Sampson taking off from HMS Hibernia 14 months later. His work on seaplanes was just slightly behind the French (January 1911 as compared to March 1910) and was followed by the British in December 1911 (they also apparently bought some of Curtis's Triad floatplanes). His first flying boat was built in collaboration with a British Naval officer and didn't fly until June 1914, it was then quickly taken up by the British who also built them and improved on them themselves, in collaboration with Curtis.

Basically I am not sure there is any place where Curtis's work could be disseminated and absorbed in such a way that would significantly improve the speed of adoption over OTL. There are almost certainly some missed opportunities in every countries early aeroplane development, but nothing that sticks out as a single massive inflection point from Curtis. Certainly not one that would allow the British to count on masses of aircraft as a scouting force prior to the outbreak of war.

 

[McPherson]

Basically I am not sure there is any place where Curtis's work could be disseminated and absorbed in such a way that would significantly improve the speed of adoption over OTL. There are almost certainly some missed opportunities in every countries early aeroplane development, but nothing that sticks out as a single massive inflection point from Curtis. Certainly not one that would allow the British to count on masses of aircraft as a scouting force prior to the outbreak of war.

USN 1918.

 

[I want to learn]

True, and that very well could have happened with the Swifts as well. The concept was somewhat unproven. However, IOTL it was realized that a submarine control ship was needed in the Heligoland Bight after war broke out. These were the fleet destroyers Firedrake and Lurcher. They were not ideal for the purpose and Keyes spent some time trying to get an Arethusa class cruiser instead. To be honest, an Arethusa might have been just as bad for the role.

Here is John's description of the Swift/Super-Swift development paradigm. He probably describes it better than I do:

IIRC the discussion of "super-Swifts" came up on alltheworldsbattlecruisers in the context of the genesis of the Courageous class cruisers. As the quote you posted lays out, the technology for a small warship to consistently outrun a medium/big warship didn't exist in the 1910s. Fisher was probably to right to push for such a ship, but it just wasn't technologically possible. What he had built instead were the Renown and Courageous classes, which were indeed enough to bully enemy light cruiser squadrons and evade the rest. However IOTL those ships were distinctly not used as submarine squadron flagships. Perhaps they would have been more useful in that role, but I'm skeptical.

Sorry for the late response.

Thanks so much for your very detailed reply!

However, the situation is different in 1914, which is what I think you're talking about.

Right I'm wondering how things might have developed if the British had a different attitude with regards to the Danish straights.

I don't think the British would protest the mining of the Great Belt against the British, which was done by Danish ships on behalf of Germany.

Was the mining of the Great Belt done exclusively by Danish ships? This link describes that the Germans began mining the Great Belt on August 5th, followed by an ultimatum to the Danes telling them to follow suit. The Danes acquiesced, but it seems like there was some confusion even among the Danes about the status of those minefields, what with the kings telling each other they weren't armed. It's not even clear to me that the British knew there were German minefields involved. If there had been a Royal Navy destroyer flotilla or cruiser squadron lurking in Denmark's seas on August 5th providing the British government more accurate intelligence, I assume the mining of Danish waters would be much more contentious, and possibly have resulted in German attempts at occupying Denmark. Alternatively, (if the British had a pre-war plan to launch an offensive into the Baltic) a Royal Navy fleet might sail straight into a Danish minefield they thought was unarmed.

A British operation in the Baltic in the fall of 1914 could have happened, and in the situation where Denmark is forced to take a side as a combatant, I think that King would simply dismiss the government and join the British.

Do you think Denmark would have joined the British regardless of the circumstances? I mean I would think it's one thing if Germany invades Jutland because there's a British squadron coaling in Aarhus, and it's another if a British troop convoys shows up demanding the keys to Copenhagen's fortifications; at least I assume so. Also, do you have any idea what level of Royal Navy activity in the Kategatt in 1914 would have prompted Germany to invade?

 

[I want to learn]

To get back to the OP (and apologies for drifting so far on it), Based on the plans I posted earlier and the excellent summary by @Admiral Fisker the most reasonable scenario of a British invasion of Denmark seems to be if the British try to get into the Baltic in 1914. This triggers the German occupation of Jutland, which causes the King to dismiss the government and resist the Germans. This could trigger some variant of the British Plan D landing in support of the Danish.It does have some holes though. The British Army had basically shut down any idea of combined operations in 1911. They were pretty committed to a continental strategy.

Well I don't know if British Plan D (from post #232) is a necessary prerequisite. What I'm imagining (and this is reverse-engineering the POD a bit) is the British just not writing off the Danish straights. This leads to a skirmish at sea between British and German naval forces in Danish waters, which triggers German invasion of Jutland, but there's no German amphibious capacity to invade Zealand, which the British then gradually reinforce. Then both sides try launching island-hoping campaigns throughout the Danish archipelago heavily supported by their respective naval forces...sort of like Gallipoli if the Turks had a real navy and attempted a counter invasion of Mudros and Lemnos.

 

[Coulsdon Eagle]

Interestingly Holger Herwig in Luxury Fleet: The German Imperial Navy 1888-1918 has references to the British Admiralty's realisation that even if the RN penetrated into the Baltic, they feared that the Germans would close the Great & Little Belts behind the RN with blockships, leaving them trapped (for a period, anyway) in the Baltic. While this refers to 1917, it wasn't a possibility we had considered for 1914, concentrating upon not allowing the British through the Danish archipelago. Would be an interesting tactic to "remove" a large part of the Grand Fleet from the North Sea.

 

[I want to learn]

Interestingly Holger Herwig in Luxury Fleet: The German Imperial Navy 1888-1918 has references to the British Admiralty's realisation that even if the RN penetrated into the Baltic, they feared that the Germans would close the Great & Little Belts behind the RN with blockships, leaving them trapped (for a period, anyway) in the Baltic. While this refers to 1917, it wasn't a possibility we had considered for 1914, concentrating upon not allowing the British through the Danish archipelago. Would be an interesting tactic to "remove" a large part of the Grand Fleet from the North Sea.

I doubt the capital ships of the Grand Fleet would venture into the Baltic proper unless their rear was secure, and maybe not even then. To fend off German amphibious landings on Zealand the British only need to commit light forces like submarines and destroyers and/or second line units like reserve fleet pre-dreadnoughts. Also, is the Little Belt even navigable to large warships even in peace time? Even if those two straights were closed there is the Øresund, which I think is just barely navigable to large ships, and is farther from the German bases in Kiel which blockships would likely sortie from.

 

[Coulsdon Eagle]

I doubt the capital ships of the Grand Fleet would venture into the Baltic proper unless their rear was secure, and maybe not even then. To fend off German amphibious landings on Zealand the British only need to commit light forces like submarines and destroyers and/or second line units like reserve fleet pre-dreadnoughts. Also, is the Little Belt even navigable to large warships even in peace time? Even if those two straights were closed there is the Øresund, which I think is just barely navigable to large ships, and is farther from the German bases in Kiel which blockships would likely sortie from.

Apparently the Admiralty did not consider the Oresund capable of allowing larger warships through, although I daresay there was a fair bit of leeway given, and probably a calculation based upon the maximum speed that could be used.

If looking to fend off a German invasion of Copenhagen then likely the RN would wish to penetrate into the Baltic to attack German LoCs.

Still, I agree with you on above, and still feel that any RN effort to get through the Danish archipelago would have been a grave & expensive error.

 

[I want to learn]

If looking to fend off a German invasion of Copenhagen then likely the RN would wish to penetrate into the Baltic to attack German LoCs.

I think submarines and torpedo boats would be the main instruments of naval warfare in the Kattegat and western Baltic. (Of both sides)

Still, I agree with you on above, and still feel that any RN effort to get through the Danish archipelago would have been a grave & expensive error.

Putting the British battle fleet would have been a bad idea, but saying any effort to get into the Baltic is an error isn’t quite right. I think Baltic Submarine flotilla was basically worthwhile IOTL. Holding Zealand/Copenhagen and command of the Oresund means RN submarines have a much easier time getting in, and light cruisers and destroyers sorties are practical.

Additionally, while the Grand Fleet might not want to go in the Baltic, there might be some interest in letting the four new dreadnoughts of the Russian fleet out of the Baltic. AIUI those Russian ships were commissioned right around January 1915, the time Jellicoe’s numeric superiority was most tenuous, and even at other times the Gangut class didn’t do much for Russia holed up in the Gulf of Finland.

 

[Coulsdon Eagle]

Problem with torpedo boats is they will need a base for refuelling & rearming, as their operational range is not great.

Don't believe the Gangut's have a great operational range either, and in the western Baltic more likely to run into numerically stronger HSF battlesquadrons who would have time to redeploy through the Kiel Canal. Any attempted coordination with the RN would require agreement on calendar to be used!

Russian fleet in being did require overkill when the HSF did go east, such as Operation Albion, even if the dreadnoughts never left the Gulf of Finland. Not sure if I was in Petrograd or Helsinki I would want them traipsing through the North Sea when Scheer comes calling.

Doing the maths, RH outnumbered HSF roughly 2:1 in dreadnoughts by 1918 whereas the HSF outnumbered the Russian Baltic Fleet 5:1

 

[I want to learn]

Problem with torpedo boats is they will need a base for refuelling & rearming, as their operational range is not great.

Don't believe the Gangut's have a great operational range either

That’s the attraction of having Copenhagen as a base.

western Baltic more likely to run into numerically stronger HSF battlesquadrons who would have time to redeploy through the Kiel Canal

If the German battlefleet wants to sortie from Kiel into the Baltic they’d have to pass through the narrow Fehmarn Belt which would probably be heavily mined and is a choke point for Royal Navy destroyers from Copenhagen to attack capital ships in. Ships passing through might even be in range of coastal defense artillery on Lolland. The HSF would be observed when it sortied and the Russian squadron could turn for home as necessary. Then when the HSF tries to return to Kiel all sorts of dangerous things could happen when they try to go back in; submarine pickets, torpedo boat ambush, blockships sunk in the Fehmarn Belt, new minefields…sortieing into the Baltic becomes almost as hazardous for the HSF as it is for the Grand Fleet.

Any attempted coordination with the RN would require agreement on calendar to be used!

Lol true. I thought the Black Sea fleet made some gestures of coordination during the Gallipoli campaign at least though?

Russian fleet in being did require overkill when the HSF did go east, such as Operation Albion, even if the dreadnoughts never left the Gulf of Finland. Not sure if I was in Petrograd or Helsinki I would want them traipsing through the North Sea when Scheer comes calling.

Fair enough, but even without Russian dreadnoughts is Kronstadt really going to fall to naval assault? I mean Gallipoli failed and the Allies pretty much had naval supremacy. Even if the Germans *think* direct attacks on sea fortresses is a viable strategy (questionable), that line of thinking would lead them to realize Heligoland is vulnerable if they commit their fleet to the Baltic.

 

[Coulsdon Eagle]

Tuned into a WFA lecture last night given by author & noted naval historian Andrew Lambert on... Admiral Fisher, the Baltic, and British Grand Strategy.

While I don't agree with his general thrust, which was that Britain should not send any troops to the Western Front, and leave the Dardanelles well alone, he brought up some interesting points that relate to this thread.

Julian Corbett had developed a grand strategy based upon maritime warfare (not just restricted to naval warfare). This was junked at a meeting on 5(?) August when the war cabinet, 4 generals & 1 admiral decided to send the BEF to France. The main mover of this was the First Lord of the Admiralty, WS Churchill (Lambert is not a fan) so the sole admiral shut up.

Fisher believed that blockading Germany's Baltic coast would be a major economic victory as the trade with Sweden would be interrupted - I know little about this Baltic trade but Fisher & Corbett believed in it.

Fisher believed that before any action was possible on the Baltic, the Belgian coast as far as the Scheldt needed to be cleared, either by the Army alone or in conjunction with naval support or amphibious assault.

For the descent upon Belgium, and the Baltic foray, Fisher did not intend using the Grand Fleet except in a distant covering role. Instead a new fleet would be built, consisting of monitors (with latest fire control directors), X-lighter (armoured landing craft), specially converted old cruisers (e.g. Grafton), mine sweepers & mine bumpers, and large light cruisers able to pass through the Little Belt, Great Belt or the Sound at speed i.e. Courageous, Glorious or Furious.

Fisher had previously managed an unannounced RN battle squadron unexpected visit to German waters around the time of the Russo-Japanese War, leading the Germans to believe he would try to "Copenhagen" their fleet - not heard of this before but Swinemunde was the port mentioned.

He hoped that his past history and his public utterances, and the obvious preparations, would lead the Germans to launch a pre-emptive invasion of Denmark, which would allow the British to join the Danes in defending their neutrality (while gaining access to the Baltic) and possibly bring Sweden into the war on the Entente side. He had plans for new "Lines of Torres Vedras" defending Copenhagen on Zeeland.

At the end the last question allowed developed into a "nothing I've heard in the last hour convinces me your strategy would work" from a Western Front zealot.

Should be available to view on the WFA website if you are a member.

That’s the attraction of having Copenhagen as a base.

Yes - first, catch your hare! Getting Copenhagen is the issue; supplying it with British torpedoes, shells, etc. would be another problem.

If the German battlefleet wants to sortie from Kiel into the Baltic they’d have to pass through the narrow Fehmarn Belt which would probably be heavily mined and is a choke point for Royal Navy destroyers from Copenhagen to attack capital ships in. Ships passing through might even be in range of coastal defense artillery on Lolland. The HSF would be observed when it sortied and the Russian squadron could turn for home as necessary. Then when the HSF tries to return to Kiel all sorts of dangerous things could happen when they try to go back in; submarine pickets, torpedo boat ambush, blockships sunk in the Fehmarn Belt, new minefields…sortieing into the Baltic becomes almost as hazardous for the HSF as it is for the Grand Fleet.

Probably mined by the Germans first.

Lol true. I thought the Black Sea fleet made some gestures of coordination during the Gallipoli campaign at least though?

They were supposed to make a demonstration but not sure of the date. The Turks never used their fleet (minelayers, destroyers / TBs or subs apart) against the invasion fleet.

Fair enough, but even without Russian dreadnoughts is Kronstadt really going to fall to naval assault? I mean Gallipoli failed and the Allies pretty much had naval supremacy. Even if the Germans *think* direct attacks on sea fortresses is a viable strategy (questionable), that line of thinking would lead them to realize Heligoland is vulnerable if they commit their fleet to the Baltic.

No, it should not fall, but would any Russian commander send his battle fleet hundreds of miles away from a front that is moving towards their capital? Well, to be fair, the last Baltic Fleet ended up a long, long way from home! You do need the dreadnoughts to at least provide distant cover for your minefields, or the Germans can just send their minesweepers into the Gulf of Finland with no fear of being attacked by superior forces.

Fisher believed Helgoland was impossible to assault without major fleet losses. He also ruled out the attack on Borkum so no Frisian Islands under him. The HSF was never seen as providing Helgoland's security but again cover for the minelayers and later the U-boats.

 

[I want to learn]

Yes - first, catch your hare! Getting Copenhagen is the issue; supplying it with British torpedoes, shells, etc. would be another problem.

Surely supply ships would have faced threats from raiding u-boats, but I just don't see the HSF as being capable of project enough force through the Danish straights or into the Skagerak to consistently prevent Allied merchantmen carrying armaments from reaching the Kattegat, and thus Roskilde/Copenhagen. If anything, the British get early experience with convoys. Although I don't know if Zealand was anywhere close to being self-sufficient in food, so there might be a brewing humanitarian catastrophe.

Probably mined by the Germans first.

Are you implying this would mean the Fehmarn Belt would be off limits to Allied light forces? Because I think there was some willingness to risk submarines and destroyers in a enemy minefield if there was a chance they could get a shot in on capital ships. I forget if it was Scarborough or Dogger Bank, but IIRC Beatty was ready to detach destroyers and have them ambush returning German cruisers at night inside the Heligoland Bight in accordance with the Royal Navy playbook, but the timing and/or command&control issues precluded it. See also, the consistent presence of Allied submarines in the Sea of Marmara during the Gallipoli campaign. I think the Fehmarn Belt would be closed to German capital ships for practical purposes.

They were supposed to make a demonstration but not sure of the date. The Turks never used their fleet (minelayers, destroyers / TBs or subs apart) against the invasion fleet.

I looked it up: https://en.wikipedia.org/wiki/Action_of_10_May_1915 Russian pre-dreadnoughts sortied on a mission to bombard Constantinople and encountered SMS Goeben.

You do need the dreadnoughts to at least provide distant cover for your minefields, or the Germans can just send their minesweepers into the Gulf of Finland with no fear of being attacked by superior forces.

The Russians didn't have dreadnoughts for the first ~6 months of the war, so clearly there were other factors than just dreadnoughts keeping Petrograd secure.

 

[Coulsdon Eagle]

The Russians didn't have dreadnoughts for the first ~6 months of the war, so clearly there were other factors than just dreadnoughts keeping Petrograd secure.

Well, the German Army was quite a bit further away in 1914 and not a threat to the Baltic coastline. Different when later in the war they are at the gates of Riga and the HSF seeking to push into the Gulf of Riga.

 

[Tibi088]

Surely supply ships would have faced threats from raiding u-boats, but I just don't see the HSF as being capable of project enough force through the Danish straights or into the Skagerak to consistently prevent Allied merchantmen carrying armaments from reaching the Kattegat, and thus Roskilde/Copenhagen. If anything, the British get early experience with convoys. Although I don't know if Zealand was anywhere close to being self-sufficient in food, so there might be a brewing humanitarian catastrophe.



Are you implying this would mean the Fehmarn Belt would be off limits to Allied light forces? Because I think there was some willingness to risk submarines and destroyers in a enemy minefield if there was a chance they could get a shot in on capital ships. I forget if it was Scarborough or Dogger Bank, but IIRC Beatty was ready to detach destroyers and have them ambush returning German cruisers at night inside the Heligoland Bight in accordance with the Royal Navy playbook, but the timing and/or command&control issues precluded it. See also, the consistent presence of Allied submarines in the Sea of Marmara during the Gallipoli campaign. I think the Fehmarn Belt would be closed to German capital ships for practical purposes.


I looked it up: https://en.wikipedia.org/wiki/Action_of_10_May_1915 Russian pre-dreadnoughts sortied on a mission to bombard Constantinople and encountered SMS Goeben.



The Russians didn't have dreadnoughts for the first ~6 months of the war, so clearly there were other factors than just dreadnoughts keeping Petrograd secure.

The Danish Island are very very close to the german mainland. Next door actually. How do you prevent the german (and danish) forces landing on the islands? Because any number of smaller naval forces you leave there against that can be swept aside by the much much closer HSF. The thing is: you cant really prevent german landings that close to home.

And if there is a big land battle after the germans landed the british supply lines will be very long and very vulnerable - while the german are again next door to home. I dont think the british can hold the Islands if the germans decide to liberate them.