Codeword Overlord Read online

  Cover illustrations

  Front: Beach Group troops wade ashore from landing craft on Queen beach, Sword area, on the evening of 6 June 1944. (IWM)

  Back: Erwin Rommel on an inspection of the Atlantic Wall.

  First published 2019

  The History Press

  The Mill, Brimscombe Port

  Stroud, Gloucestershire, GL5 2QG

  www.thehistorypress.co.uk

  © Nigel West, 2019

  The right of Nigel West to be identified as the Author of this work has been asserted in accordance with the Copyright, Designs and Patents Act 1988.

  All rights reserved. No part of this book may be reprinted or reproduced or utilised in any form or by any electronic, mechanical or other means, now known or hereafter invented, including photocopying and recording, or in any information storage or retrieval system, without the permission in writing from the Publishers.

  British Library Cataloguing in Publication Data.

  A catalogue record for this book is available from the British Library.

  ISBN 978 0 7509 9176 6

  Typesetting and origination by The History Press

  Printed and bound in Great Britain by TJ International Ltd

  eBook converted by Geethik Technologies

  The military organisation that has the most efficient reconnaissance unit will win the next war.

  General Werner von Frisch, 1938

  The invasion does not yet appear to be imminent.

  Field Marshal Gerd von Rundstedt, C-in-C West, 5 June 1944

  During the night and the early hours of this morning the first of the series of landings in force upon the European Continent has taken place.

  Winston Churchill, House of Commons, 6 June 1944

  A considerable degree of surprise was achieved throughout.

  Brigadier Edgar Williams, 21st Army Group, 6 June 1944

  The Allies scored a great surprise on 6 June 1944 by the imposition of radio silence.

  General Albert Praun, OKW Chief Signal Officer

  CONTENTS

  Acknowledgements and Author’s Note

  Glossary and Abbreviations

  Introduction

  Dramatis Personae

  1 OVERLORD

  2 German SIGINT

  3 Luftwaffe Aerial Reconnaissance

  4 Protecting OVERLORD

  5 The Iberian Front Line

  6 BODYGUARD Spies

  7 The Intelligence Assessment

  8 The Rommel Analysis

  9 MUSGRAVE

  10 Phase II

  11 Stay-Behind

  Postscript

  Appendix I Führer Directive No. 51, Dated 3 November 1943

  Appendix II Baron Oshima’s Inspection of the Atlantic Wall, October 1943

  Appendix III FUSAG Components

  Notes

  Select Bibliography

  ACKNOWLEDGEMENTS AND AUTHOR’S NOTE

  The author acknowledges his debt of gratitude to those who have assisted his research, among them the late Bill Williams, Roger Hesketh, David Strangeways, Noel Wild, Juan Pujol (GARBO), Roman Garby-Czerniawski (BRUTUS), Harry Williamson (TATE); Frano de Bona (FREAK); Ib Riis (COBWEB) Dusan Popov (TRICYCLE); Elvira de la Fuentes (BRONX), Lisel Gärtner, Hugh Astor, Christopher and Pam Harmer, Cyril Mills, Desmond Bristow, Tommy and Joan Robertson, Russell Lee, Bill Luke, Philip Johns, Cecil Gledhill, Kenneth Benton, John Codrington, Brian Stonehouse, Tony Brooks, Ladislas Farago, Gunter Peis, David Kahn, Jack Beevor, Anthony Coombe-Tennant, Vera Atkins, Rob Hesketh and Bill Cavendish-Bentinck. Also Marco Popov, Jennifer Scherr and Christopher Risso-Gill.

  Many of the documents reproduced in this volume originate from official files and have been redacted during the declassification process. Where possible the redactions have been restored, but where this has not been possible the redaction is indicated thus: [XXXXXXXXXXXXXXXX]

  The author has retained the convention of printing code names in capitals but, for ease of reading, has restored capitalised surnames to ordinary, lower case.

  GLOSSARY AND ABBREVIATIONS

  AA

  Anti-Aircraft

  Abt

  Abteilung

  AFU

  Agentfunkgerät

  Amt

  Office

  APO

  US Army Post Office

  Army Group B

  Commanded by Erwin Rommel

  B-Dienst

  Beobachtungdienst

  B1(a)

  MI5 section handling double agents

  B1(g)

  MI5’s Spanish section

  BCRA

  Bureau Central de Renseignements et d’Action

  BEF

  British Expeditionary Force

  BJ

  BLACK JUMBO diplomatic decrypt

  CENTRO

  KO Madrid’s wireless station

  COMZ

  Communications Zone

  COSSAC

  Chief of Staff to the Supreme Allied Commander

  CSDIC

  Combined Services Detailed Interrogation Centre

  CW

  Continuous Wave

  DB

  Director, B Division MI5

  DGS

  Dirección General de Seguridad

  DOWAGER

  Ops (B) in Italy

  DSO

  Defence Security Officer

  FA

  Reichsluftfahrtministerium Forschungsamt (Foreign Ministry Research Office)

  FAK

  Nachrichten Fernaufklaerungs Kompanie (Long-range intercept company)

  Feste

  Feste Nachrichten Aufklärungsstelle (stationary intercept company)

  FHW

  Fremde Heere West

  Fnu

  First Name Unknown

  FSS

  Field Security Section

  FU III

  Funkabwehr

  FUSAG

  First United States Army Group

  GC&CS

  Government Code & Cipher School

  GIS

  German Intelligence Service

  GPO

  General Post Office

  GRT

  Gross Registered Tonnage

  GSP

  Gibraltar Security Police

  H Gp B

  Heere Group B

  Hoeh Kdr D Na

  Hoeherer Kommandeur der Nachrichten Aufklaerung (Senior Communications Intelligence Officer)

  I-H

  Eins Heer

  I-L

  Eins Luft

  I-M

  Eins Marine

  ISOS

  Abwehr decrypts

  JIC

  Joint Intelligence Committee

  JMA

  Japanese military attaché decrypts

  KO

  Kriegsorganisation

  KONA

  Kommandeur der Nachrichtenaufklärung

  LCI

  Landing Craft Infantry

  LCP

  Landing Craft Personnel

  LCS

  London Controlling Section

  LCT

  Landing Craft Tank

  LN Rgt

  Luftnachrichten Regiment

  MI 14

  German order of battle section in the War Office

  MI5

  British Security Service

  MI6

  British Secret Intelligence Service

  MoI

  Ministry of Information

  MP

  US Army Military Police

  MSS

  Most Secret Sources

  NKVD

  Soviet intelligence service

  OB West

  Oberbefehlshaber West

  OKH/Chi

  Oberkommando des Heeres, Chiffr
ierabteilung

  OKH/GdNA

  Oberkommando des Heeres, General der Nachrichten Aufklaerting

  OKL/LN

  Luftnachrichten

  OKM/SKL III

  Seekriegsleitung III

  OKW

  Oberkommando der Wehrmacht

  OKW/Chi

  Oberkommando der Wehrmacht, Chiffrierabteilung

  OSS

  Office of Strategic Services

  PCO

  Passport Control Officer

  Pers Z Chi

  Personal Z Chiffrierdienst des Auswärtigen Amtes

  Pers Z S

  Personal Z Sonderdienst des Auswärtigen Amtes

  PF

  Personal File

  PR

  Photographic Reconnaissance

  PVDE

  Polícia de Vigilância e de Defesa do Estado

  PWE

  Political Warfare Executive

  RHSA

  Reich Security Agency

  RSS

  Radio Security Service

  SD

  Sicherheitsdienst

  SIA

  Servizio Informazioni Aeronautica

  SIGINT

  Signals Intelligence

  SIM

  Servicio de Información Militar

  SIPO

  Sicherheitspolizei

  SIS

  British Secret Intelligence Service

  SIS

  Italian Speciali Servizio Informazioni

  Skl

  Seekriegsleitung

  SOE

  Special Operations Executive

  SOS

  US Army Services of Supply

  V-Mann

  Verbindungsmann

  WOC

  War Office Cipher

  X-2

  Counter-intelligence branch, OSS

  XX

  Twenty Committee

  Y

  Wireless interception

  INTRODUCTION

  Seventy-five years ago, on 6 June 1944, 168,000 Allied troops stormed ashore on the beaches of Normandy to begin the liberation of Nazi-occupied Europe, supported by 12,000 aircraft and nearly 7,000 ships. The invasion plan, initially code-named OVERLORD and then designated NEPTUNE and a dozen other subordinate components, was the largest amphibious assault ever contemplated, and was an extraordinarily high-risk enterprise.

  The daunting requirement to deliver a large number of heavily armed soldiers, and their supporting weaponry, to a well-defended coastline imposed significant challenges. The key to success would be the element of surprise, but the enemy was fully aware that an invasion attempt was probable sometime during the summer of 1944. The only issues at stake were the precise timing, and the exact location. If the ultimate Allied objective was to cross the Rhine, occupy the industrial assets of the Ruhr and reach Berlin, the most direct route seemed obvious.

  Conventional military doctrine dictated that the invading forces should be at sea for a minimum period, so as to avoid a major naval engagement in which the convoys of troopships would be bound to suffer heavy losses. The less time the troops were afloat, the smaller the chance of a U-boat attack, of convoys blundering into a minefield, or of discovery by an E-boat patrol, maritime picket or by aerial reconnaissance. These and similar considerations dictated that the most propitious route would be across the shortest distance, the 23 miles from the Kent ports to the Pas-de-Calais. As regards timing, the tides, moon and weather would be crucial.

  Such a plan enjoyed many merits, including the opportunity to provide maximum air cover over the combat zone, with Allied aircraft requiring only the minimum time to return to base to refuel and rearm. Considering that a fully equipped Spitfire only carried enough ammunition to fire its .303 Browning machine guns for less than twenty seconds, this factor was likely to be mission-critical, especially as ground support and air superiority would be absolutely vital in seizing and holding any beachhead.

  Another significant necessity was the logistical resupply, involving armour, food, fuel, ammunition and transport. Past experience of beach landings had demonstrated the need to capture a medium-sized, deep-water port, with its handling facilities intact. This was a tall order, but the Calais region boasted several such towns, including Dunkirk and Boulogne, and opened up the possibility of cargo ships sailing directly from the United States.

  Finally, there was a political dimension that would influence German thinking, but was unknown to the Allies. Adolf Hitler had often spoken publicly about his intention to unveil innovative new secret weapons that had a war-winning potential, and had intended a V-1 offensive for October 1943, but his scheme went awry through the intervention of Allied bombers that delayed Volkswagen’s production of the doodlebug missiles that were to be deployed in northern France in a ruthless terror campaign to flatten London. Thousands of these pulsejet-powered weapons were to be catapulted against the city from the middle of June 1944, at a rate of seventy-two per day from 104 ramps, and the German High Command (OKW) anticipated that the scale of the air offensive would force the British War Cabinet to make the elimination of the launch sites an overriding strategic priority. Indeed, Hitler predicted at a staff conference that his secret weapons would generate enough political pressure to force Churchill from office.

  The Germans knew that there was very little to be done to prevent that V-1 from reaching the capital, and that there was absolutely no defence against the V-2 ballistic missile. By the end of the war the British Civil Defence authorities had logged 5,823 flying bomb incidents, of which 2,242 landed on London, killing 6,184 civilians and 3,917 members of the armed services. A further 17,981 civilians and 1,939 servicemen were injured, and 23,000 homes destroyed.

  Hitler understood the strategic implications of allowing a beachhead to be gained, and on 3 November 1943 he had issued Führer Directive 51 (see Appendix I) to prepare for what he saw as the coming Allied offensive. However, Field Marshal Rommel’s preferred solution was a swift armoured counter-attack mounted by some of the ten Panzer divisions already garrisoned in France.

  The Allies’ masterplan was devilishly complex, involving the embarkation of troops at eleven different south coast ports, from Falmouth in the west to Newhaven in the east, destined for the five designated beaches in Normandy. In recognition of what might go awry, they deployed fifteen hospital ships, staffed by 10,000 doctors, and prepared 124,000 beds for potential casualties.

  When weighed objectively, taking into account all the relevant military and political considerations, it seemed obvious that if the Allies were to have the slightest chance of overwhelming Rommel’s so-called impregnable Atlantic Wall, manned by fifty-eight divisions of the 7th and 15th Armies, they would have to assemble in south-east England and rush across the Channel to Calais during the full moon, at high tide, perhaps relying on a diversionary attack elsewhere to draw the defenders in the wrong direction.

  Of course, we now know that the focus of D-Day was in Normandy, and that in the absence of any available ports the Allies constructed two huge MULBERRY harbours off the beach where the pontoons were protected by sunken block-ships acting as breakwaters. Innovative engineers also designed and installed an underwater fuel pipeline code-named PLUTO (‘pipeline under the ocean’), laid on the seafloor from Niton in the Isle of Wight, to sustain the invasion vehicles, thus reducing the need for vulnerable tankers to make the long voyage from Plymouth or Southampton in seas likely to be infested by an estimated 125 U-boats1.

  For many years much secrecy surrounded the concept of strategic deception, but a series of disclosures in the 1970s revealed that a group of ingenious American and British planners had persuaded the Allied Supreme Commander, General Dwight D. Eisenhower, that a gamble on Normandy in preference to the more obvious choice, might catch the enemy off guard and enable a sizeable beachhead to be achieved before encountering the danger of counter-attack. The argument was that the OKW was predisposed to accept the Pas-de-Calais as the only sensible invasion objective, and the Allies
possessed the means to reinforce this judgment by providing the necessary evidence. Indeed, the deception planners exercised control over the enemy’s network of spies, had access to his most confidential communications, enjoyed air superiority and could impose the very strictest security conditions on the British Isles that could not be matched anywhere on the Continent with its porous land frontiers. These factors combined to create a unique set of circumstances that could be exploited by an intelligence community that had experimented with deception schemes in the Mediterranean and Middle East to gain unprecedented experience of the art of misdirecting the Axis. The results achieved in those theatres suggested that skilful, co-ordinated manipulation of wireless traffic, double agents and camouflage could accomplish much by exaggerating strengths, disguising weaknesses and confusing the adversary.

  The gamble, concealed by the codeword BODYGUARD, was momentous in every respect. Experience gained at Dunkirk, Dieppe, North Africa, Sicily, Salerno, Anzio, Attu and Kwajalein showed that Allied troops were at their most susceptible when they made their way ashore in slow, poorly protected landing craft, to then negotiate the beach obstacles and evade the lethal crossfire from heavily fortified installations manned by seasoned veterans of the Russian front. The implications of a major defeat on the Cherbourg peninsula, with the invaders pushed back into the sea, would be dire, and certainly delay any further attempt for another year. Following his victory, Hitler would be free to move reinforcements to the east, and he would also have the benefit of the V-1 and V-2 onslaught. Perhaps, with his stock high, the Wehrmacht would not have been motivated to attempt a coup on 20 July, and he might have bought sufficient time, maybe an extra two years, to develop jet fighters and invest in an atomic bomb. This is sheer speculation, but such conjecture gives some context to what was riding on the chance to free Europe from Nazi tyranny.