Alexis von Roenne and the doubling of estimates of Allied strength before OVERLORD

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Juan G. C.
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Alexis von Roenne and the doubling of estimates of Allied strength before OVERLORD

#1

Post by Juan G. C. » 11 Apr 2021, 20:01

As I have found no section about intelligence, I post this thread here. I have read in several sources an odd story about Alexis von Roenne and the estimates of Allied strength in Britain and I wanted to check its truth, for it seems incredible. According to this story, colonel Alexis von Roenne, chief of the Fremde Heere West, and his subordinate Roger Michel found in early 1944 that the estimates of the Allied strength in Britain were being halved by the SD before presenting them to Hitler and the other military authorities. In order to ensure that the correct data reached Hitler, they decided to multiply by two their assessments of allied strength, so that when the SD should halve the estimates, they would be correct. But without their knowledge the SD stopped halving the estimates, and so Hitler and the german commanders received the estimates of Allied strength doubled.

This story seems, as I said, incredible, and it seems to ignore the existence of Operation Bodyguard and Fortitude (although practically all the books where I have read it deal with them, even extensively), which, if I'm not mistaken, were already making the Germans believe the Allies had much more forces in Britain than they really had, even before this supposedly happened. But I have found it repeated in many places. Is there any truth in this story? Can it be confirmed or given the lie? Thanks and best regards.

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Re: Alexis von Roenne and the doubling of estimates of Allied strength before OVERLORD

#2

Post by Carl Schwamberger » 12 Apr 2021, 03:55

Probably more complicated than that, butI don't recall a lot of details about this intel effort. In general they were collecting information that included Allied deception op FORTITUDE. The fake radio messages of FUSAG being the principle. Theres not much evidence all the inflatable fake vehicles were counted, or other visual deception items were observed. The LW did not fly many air photography missions over south England in March and April, and effectively none in May. I don't know if Roenne was receiving the inelligence fed via the Double Cross system, but there was a lot of information about nonexistent combat formations in that. Hitler ate it up, thinking he had a successful spy network in England.

Anyway a portion of the over count came from the false FORTITUDE/FUSAG message traffic.


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Re: Alexis von Roenne and the doubling of estimates of Allied strength before OVERLORD

#3

Post by Juan G. C. » 12 Apr 2021, 09:01

I have another problem with this story. Colonel von Roenne was executed in 1944 for knowing about the 20 July plot and not reporting it. And Roger Michel (or Michael, depending on the source) was quickly released after the war and vanished, apparently defecting to the Soviet Union, and was never seen again. So where does this story come from?

EDIT: I have found in Arne Molfenter's Garbo, der Spion: Das Geheimnis des D-Day that the story was told by Roger Michel while he was in British captivity after the war. Molfenter dismiss the story as false, as Michel's invention, and I think he is right.

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Re: Alexis von Roenne and the doubling of estimates of Allied strength before OVERLORD

#4

Post by Carl Schwamberger » 14 Apr 2021, 04:44

Allied intelligence services, including the section/s working with the Deception Committee searched out ad evaluated what they could find of Ronnes work, & other German intelligence departments. Holt refers to this in 'The Deceivers' . The Deception organization had some feedback on their efforts from ENIGMA decrypts, & they were very curious about what other sources would tell them about the German reaction. So you might look in that direction for more information on Ronne & his peers analysis.

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Re: Alexis von Roenne and the doubling of estimates of Allied strength before OVERLORD

#5

Post by Juan G. C. » 18 Apr 2021, 18:06

I have found part of what Roger Michel told the British after the war, quoted in SS-Obersturmbannführer Hubert Meyer's history of the SS Hitlerjugend Panzer Division:
Towards the end of 1943 my chief and I were called to the Heer (army) command staff at least once per month for briefings. We were always amazed by the illogical under-estimation of the Anglo/American forces and by the equally illogical over-estimation of the potential of the defending German forces in France, Norway, and the Balkans. Units were constantly deployed to other theatres of war. Based on this, my chief approved an increase in the number of British divisions in our estimates to counterbalance the much too optimistic tendency of the Heer command staff.

Our estimates were some 20 divisions too high (8 infantry divisions, named after shires or regions, 4 or 5 infantry or partly armored divisions with numbers from 900 up, 5 Canadian divisions, 7 or 8 tank divisions and 3 or 4 divisions in the Mediterranean theatre of war. I cannot remember details without reference to the brochure "The British Army in War" which I issued at the beginning of the year...

As sources to predict Anglo/American attack from Great Britain I had the usual intercepted radio messages and statements of prisoners in Italy. Particularly valuable were messages sent through the Royal Air Force network, especially when they provided information on the four Allied Armies already in action. Radio messages from the convoys en route from North America were also useful. Our infiltration of the French resistance movement also provided us with some very valuable indications and clues.

The invasion itself confirmed our picture of the enemy.
The source of this quote is, accordin to Meyer, a "File on colonel M." in British Army of the Rhine Intelligence Review, 6 March 1946. Is it possible to get access to it, in order to have the whole of what he said? For here nothing is said about the SD halving the estimates.

The fact that colonel Alexis von Roenne was later executed in connection with the 20 July plot inevitably raised suspicions, specially in Nazi circles, that he was deliberately passing information that he knew was false in order to help the Western Allies. If I remember correctly that is what David Irving says or lets understand, that he knew or at least suspected that he was being deceived. But also others accept this as a possibiIity. I find this improbable, but everything about this is pretty confused.

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Re: Alexis von Roenne and the doubling of estimates of Allied strength before OVERLORD

#6

Post by Carl Schwamberger » 20 Apr 2021, 17:12

My personal experience is intelligence collection & analaysys in any army is confusing. The oddities with Ronnes analysis look normal to me.

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Re: Alexis von Roenne and the doubling of estimates of Allied strength before OVERLORD

#7

Post by ljadw » 20 Apr 2021, 19:01

There was nothing wrong with what von Roenne said : it was and is the normal practice of intelligence services overall in the world : they all are covering their behind by increasing the enemy strength : the GRU did this in 1940/1941.On March 11 1941 Zhukov and Timochenko told Stalin that Germany and its allies could attack the USSR with 268 divisions,10800 tanks,20000 pieces of artillery and 11600 aircraft and they claimed that in March 85 German divisions were concentrated in Romania and Bulgaria .
A lot of nonsense .
At the end of the 1940s,US intelligence services and media claimed that Stalin had concentrated hundreds of divisions to attack Western Europe ,while the Soviets had demobilized and were not even able to eliminate Tito after his defection .
In 1960,the CIA invented the well-known missile gap .
And, for Roenne, there is no proof at all that the German strategy in the West was depending on,or even influenced by his reports .

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Re: Alexis von Roenne and the doubling of estimates of Allied strength before OVERLORD

#8

Post by Sheldrake » 21 Apr 2021, 00:39

Carl Schwamberger wrote:
12 Apr 2021, 03:55
Probably more complicated than that, butI don't recall a lot of details about this intel effort. In general they were collecting information that included Allied deception op FORTITUDE. The fake radio messages of FUSAG being the principle. Theres not much evidence all the inflatable fake vehicles were counted, or other visual deception items were observed. The LW did not fly many air photography missions over south England in March and April, and effectively none in May. I don't know if Roenne was receiving the inelligence fed via the Double Cross system, but there was a lot of information about nonexistent combat formations in that. Hitler ate it up, thinking he had a successful spy network in England.

Anyway a portion of the over count came from the false FORTITUDE/FUSAG message traffic.
As ever, interesting points. It is also far easier to persuade someone to believe something they already want to believe. I suspect the German assessments may have been based on their assumptions of US and British manpower mobilisation. These probably assumed a much higher proportion of fighting soldiers to service support. The Germans may have worked out that the allies could have 3.5 million men in the UK . Using their organisational templates that might have been an army of 75 divisions rather than 35 with a lot of artillery, air forces and logistics. Some of the German intelligence failure may have been due to a lack of understanding of how the allies planned to fight.

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Re: Alexis von Roenne and the doubling of estimates of Allied strength before OVERLORD

#9

Post by Carl Schwamberger » 21 Apr 2021, 06:34

ljadw wrote:
20 Apr 2021, 19:01
There was nothing wrong with what von Roenne said : it was and is the normal practice of intelligence services overall in the world : ...On March 11 1941 Zhukov and Timochenko told Stalin that Germany and its allies could attack the USSR with 268 divisions,10800 tanks,
That number is not far from US Army claims in 1941 for the number of German tanks. A wartime information publication from the US Army stated 12,000 tanks were used to defeat France & its Allies.

ljadw wrote:
20 Apr 2021, 19:01
And, for Roenne, there is no proof at all that the German strategy in the West was depending on,or even influenced by his reports .
A item Holt takes a brief look at in his 'Deceivers'. He mentions how post 1944 British counter intelligence officers tried to reconstruct Ronnes material, to evaluate the effect of various intel & deception ops. They reported a lot of material collected, but less completely analyzed than they expected, and little influence on OKW. The latter had become so enamored with what their spy network in the UK had been reporting OKW was barely looking at Ronnes groups reports.

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Re: Alexis von Roenne and the doubling of estimates of Allied strength before OVERLORD

#10

Post by Juan G. C. » 22 Apr 2021, 08:16

ljadw wrote:
20 Apr 2021, 19:01
And, for Roenne, there is no proof at all that the German strategy in the West was depending on,or even influenced by his reports .
Carl Schwamberger wrote:
21 Apr 2021, 06:34
A item Holt takes a brief look at in his 'Deceivers'. He mentions how post 1944 British counter intelligence officers tried to reconstruct Ronnes material, to evaluate the effect of various intel & deception ops. They reported a lot of material collected, but less completely analyzed than they expected, and little influence on OKW. The latter had become so enamored with what their spy network in the UK had been reporting OKW was barely looking at Ronnes groups reports.
Holt himself says that "for intelligence about the Western Allies, the Wehrmachtführungsstab relied chiefly on the intelligence staff of the High Command of the Army , the Oberkommando des Heeres, or OKH ; and specifically on a branch of OKH known as Foreign Armies West , Fremde Heere West , or FHW [headed by Roenne]".

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Re: Alexis von Roenne and the doubling of estimates of Allied strength before OVERLORD

#11

Post by ljadw » 22 Apr 2021, 12:17

That the WFS relied chiefly on FHW for intelligence about the Western Allies, does not mean that the reports of FHW were influencing German strategy in the West .
Germany had to defend the coasts of Western Europe:if there were no German units on the South coast of France, the Wallies would invade the South of France .
Besides, the number of Wally divisions was of minor importance :if they had 49 divisions, they would not land with 49 divisions on D Day, the same if they had 89 divisions .
In the HTL,it took weeks before all available Wally divisions had landed in Normandy .It would even last longer in the ATL .
The German strategy was determined by their own strength, not by the number of Wally divisions .
The US strategy in Desert Storm was not determined by what they knew about the Iraqi army, but by their own strength and by political considerations = to win as fast as possible with as less casualties as possible .

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Re: Alexis von Roenne and the doubling of estimates of Allied strength before OVERLORD

#12

Post by Juan G. C. » 22 Apr 2021, 13:20

ljadw wrote:
22 Apr 2021, 12:17
That the WFS relied chiefly on FHW for intelligence about the Western Allies, does not mean that the reports of FHW were influencing German strategy in the West .
Germany had to defend the coasts of Western Europe:if there were no German units on the South coast of France, the Wallies would invade the South of France .
Besides, the number of Wally divisions was of minor importance :if they had 49 divisions, they would not land with 49 divisions on D Day, the same if they had 89 divisions .
In the HTL,it took weeks before all available Wally divisions had landed in Normandy .It would even last longer in the ATL .
The German strategy was determined by their own strength, not by the number of Wally divisions .
The US strategy in Desert Storm was not determined by what they knew about the Iraqi army, but by their own strength and by political considerations = to win as fast as possible with as less casualties as possible .
But they did influence German strategy in the West. The fact that the Germans believed the Western Allies had an Army Group in Dover, greater than the 21st Army Group, made them think that the main landings would take place on the Pas de Calais, and that if they landed un Normandy it would be a diversión, even if a big one. And after the landings, comparing the strength and forces the Western Allies were using against Normandy with those the Germans believed the W. Allies did had on England confirmed their belief that the Allies were going to land in another place with stronger forces. This affected how they deployed their forces and how many of them they used against the Normandy beachead.

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Re: Alexis von Roenne and the doubling of estimates of Allied strength before OVERLORD

#13

Post by ljadw » 22 Apr 2021, 15:53

I like to see that the WFS/Hitler believed in July 1944 that the main landing would happen at the Pas de Calais and that this influenced their strategy = that 15 th Army was tied in July at the Pas de Calais because they believed that the real landing would happen there .
A part of the 15th army was transferred to Normandy after June 6 ,that no more forces were going to Normandy was because it was impossible to transfer them to Normandy and because if all Germans left the Pas de Calais, the Wallies would land there and this would happen whatever the Wally strength was in the UK .
A Wally landing in the Pas de Calais depended NOT on the number of divisions they had available but on the possibility of the RN to supply two landings at the same time and on the number of enemy forces .It is not that if the Wallies had 89 divisions in Britain,they could land on 2 different places .
The LSS, although not operational , was going to Normandy, not to the Pas de Calais .
The big danger/problem was not which of both landings would be the main landing ,but that Germany had not the forces to counter successfully 2 landings ,which means that the first one (diversion or not ) had priority .
Normandy had to be eliminated before a second landing could happen .That's why Das Reich, 2 Panzer,etc went to Normandy, not to the Pas de Calais .
The German strategy was : first things first .

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