We March Against England: Operation Sea Lion, 1940-1941 (Osprey General Military)

402 Pages·2016·1.27 MB·English

by  Robert Forczyk

We March Against England

We
MARCH
AGAINST
ENGLAND
Operation Sea Lion, 1940–41
Robert Forczyk
This electronic edition published in 2016 by Bloomsbury Publishing Plc
First published in Great Britain in 2016 by Osprey Publishing,
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© 2016 Robert Forczyk
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of this Work.
ISBN HB: 978 1 4728 1485 2
PDF ISBN: 978 1 4728 1486 9
ePub ISBN: 978 1 4728 1487 6
Index by Zoe Ross
Cartography by Bounford.com
Typeset in Adobe Garamond Pro
Originated by PDQ Media, Bungay, UK.
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Imperial War Museum Collections 
Many of the photos in this book come from the Imperial War Museum’s huge collections which cover all aspects of
conflict involving Britain and the Commonwealth since the start of the twentieth century. These rich resources are
available online to search, browse and buy at www.iwm.org.uk/collections. In addition to Collections Online, you can
visit the Visitor Rooms where you can explore over 8 million photographs, thousands of hours of moving images, the
largest sound archive of its kind in the world, thousands of diaries and letters written by people in wartime, and a huge
reference library. Imperial War Museum www.iwm.org.uk.
Contents
Introduction 6
Chapter 1: Strategic Setting, June–July 1940 14
Chapter 2: Improvising an Invasion Force 66
Chapter 3: Diplomacy, Espionage and Intelligence 82
Chapter 4: Kriegsmarine and Luftwaffe Capabilities Against England,
1940–41 129
Chapter 5: Countdown to Sea Lion 189
Chapter 6: British Anti-invasion Capabilities, 1940–41 199
Chapter 7: Feasibility of S-Tag, 25 September 1940 238
Chapter 8: The Isle of Wight Gambit 268
Chapter 9: Siege Operations against Great Britain, October
1940–May 1941 275
Chapter 10: Sea Lion Redux, May 1941 287
Chapter 11: Hidden Benefits of Sea Lion: Germany Gains an
Amphibious Capability for other Theatres 293
Chapter 12: The Reckoning 304
Glossary 309
Appendices 310
Notes 336
Bibliography 353
Index 357
Introduction
After winning a stunning victory in France in June 1940, on 16 July
Adolf Hitler issued Führer Directive No. 16, which initiated
preparations for a potential invasion of England, designated as
Unternehmen Seelöwe (Operation Sea Lion). Consequently, the
German Kriegsmarine (navy) and Heer (army) began improvising an
invasion fleet, initially by gathering large numbers of river barges and
small motor vessels and assembling them in the occupied Channel
ports. Regarding air superiority as a sine qua non to ensure the success
of any amphibious operation, Hitler ordered the Luftwaffe to crush
the Royal Air Force (RAF) and obtain air superiority over the English
Channel. Yet despite two months of intensive air operations in August
to September 1940, the Luftwaffe could not defeat the RAF and Hitler
became uneasy about the Kriegsmarine’s ability to conduct Seelöwe
without adequate air cover. Furthermore, the RAF began bombing the
invasion barges in the Channel ports, inflicting considerable damage.
Unnerved by the prospect of failure, on 17 September Hitler decided
to postpone Seelöwe.
By standing firm against the Luftwaffe, ‘the Few’ of RAF Fighter
Command frustrated Hitler’s plans to invade England and thereby
inflicted the first major defeat upon the Third Reich. In short, this is the
standard orthodoxy about Operation Sea Lion and the Battle of Britain:
England saved as a result of the RAF winning a two-month air battle,
6
Introduction
and the Third Reich chastised by its first strategic defeat. This heroic
orthodoxy was promoted first by Winston Churchill and British wartime
propaganda, then in the official post-war histories. The 15th of
September was officially made a day to commemorate the Battle of
Britain and, implicitly, the day the battle was decided. The British film
The Battle of Britain (1969) reaffirmed this thesis for the general public,
by promoting the notion that the German threat to England essentially
ended after the climactic air battles on 15 September 1940. In a
memorable scene at the film’s conclusion, ostensibly depicting the day
after, RAF fighter pilots are shown sitting in lawn chairs for raids that no
longer come while, over in France, German soldiers are shown throwing
their life preservers into a huge pile – representing the cancellation of
Sea Lion. Some modern historians, such as John Keegan, have continued
to endorse the heroic orthodoxy. Keegan stated that, by defeating the
Luftwaffe over England, Great Britain remained in the war and this
outcome ‘determined the downfall of Hitler’s Germany’.1 Leo
McKinstry, another adherent of the orthodox theory, absurdly concluded
that ‘the deterrence of Operation Sea Lion was the beginning of the end
for the Reich’.2 As if to add insult to injury, the standard orthodoxy
usually includes some mention that Hitler was never really serious about
invading England and that Sea Lion was something of a Potemkin
village-type fraud. Former members of the Luftwaffe, such as fighter ace
Adolf Galland and Generalfeldmarschall Albert Kesselring, are
particularly dismissive of Sea Lion and have been used to lend credence
to the idea that the invasion preparations were nothing more than a
bluff intended to intimidate Great Britain into considering a negotiated
peace. Although Sea Lion remains an item of historical curiosity in
Britain, British historians have generally treated Sea Lion with contempt
and in absolutist terms. Peter Fleming stated that ‘Operation Sea Lion,
as planned and mounted, was doomed to failure and, had it been
launched, could only have ended in disaster’.3 Ergo, the threat of
invasion was never really a threat.
Yet the standard orthodoxy has been under attack since the 1950s,
particularly on the active role played by Fighter Command versus the
7
We March Against England
deterrent role played by the Royal Navy. Hubert R. Allen, one of ‘the
Few’ and author of Who Won the Battle of Britain? (1976), was one of
the first to openly criticize the RAF’s performance in the campaign.
Newer accounts of the Battle of Britain, such as Derek Robinson’s
Invasion 1940 (2005) and Anthony J. Cumming’s The Royal Navy and
the Battle of Britain (2010) have tried to acknowledge that Hitler’s fear
of the Royal Navy played an equally important role in frustrating
Operation Sea Lion, but still tend to fall into the trap of evaluating
events in an overly narrow and deterministic context. Max Hastings
noted that Britain might have defied the Luftwaffe in September
1940, but this did not advance the goal of defeating the Third Reich
– which was accurate, but really only an admission of the obvious.4 
While the question ‘Who won the Battle of Britain?’ has merit, it
has always seemed to me an attempt to divert attention away from the
unpleasant fact that Great Britain’s military position remained
extremely perilous long after the so-called Battle of Britain. Despite
what happened in the skies over England in mid-September 1940,
Great Britain’s military situation was far more precarious than
Germany’s for another two years. The defeat of the Luftwaffe’s large-
scale daylight raids over Great Britain only curtailed one aspect of the
Third Reich’s capabilities, but had negligible impact upon Germany’s
overall ability to inflict pain upon Britain and its people. The
mythology of the Battle of Britain and ‘the Few’ conveniently avoided
mentioning that Fighter Command was virtually impotent to stop the
Luftwaffe’s night raids during the Blitz, which killed another 14,715
civilians in the next three months, or to prevent German long-range
Fw-200 Condors from mauling convoys west of Ireland. Nor could
‘the Few’ do anything to prevent U-Boats or surface raiders from
savaging British convoys during 1940–41. Curiously, the Blitz receives
far less attention in English-language historiography than the Battle of
Britain even though it lasted three times as long. While it is true that
the presence of the Home Fleet did help to deter Hitler from
attempting an invasion in 1940, it was also relatively impotent to
prevent the growing menace of U-Boat Wolfpack attacks on convoys
8