Book Review: Britain’s Secret Defences: Civilian Saboteurs, Spies and Assassins


by Andrew Chatterton

Philadelphia: Casemate, 2021. Pp. xvi, 205+. Illus., map, append., notes, biblio., index. $37.95. ISBN: 163624100X

British Preparations for Protracted Resistance to a German Invasion

Author Chatterton, who has written extensively on Britain in the Second World War, spent a dozen years researching one of the most secret corners of the British war effort, the hitherto virtually unknown existence of hundreds of covert “stay behind” resistance cells intended to disrupt a possible German invasion.

These “Auxiliary Units” and “Special Duties Branch” volunteers were not members of the Home Guard, but mostly able-bodied, trained personnel and some others, formed into hundreds of sabotage and assassination squads based in secret bolt holes, many of which have never been discovered, across the most likely German landing areas. Their mission was to wreck havoc in the German rear, to impede their ability to sustain operations against more conventional forces in open combat.

In some ways this is a grim tale. Members of these units had not only a potentially suicide mission, but were also charged with eliminating Britons who collaborated with the invaders or who, albeit wholly innocent, possessed knowledge that might be forced out of them by torture.

Chatterton covers the inception, organization, recruiting, training, and equipping of these squads, and discusses their activities during the war, albeit that there was no invasion. He gives us looks at a number of men who formed part of these units, and their wartime experiences, as many later passed into the active force. Chatterton concludes by addressing the stand down of these special formations, and how the secrecy surrounding their existence has endured for decades. In the process, he says a little about evidence for other secret measures that are still not well documents.

What is particularly interesting about Britain’s Secret Defences, is that the Paddy Griffith’s famous 1973 wargame of Operation Sealion at Sandhurst was designed at a time when these – and other -- covert preparations for coping with a German invasion were still highly secret, making the outcome of the simulation, a decisive British victory, even more certain.

Britain’s Secret Defences is essential reading for anyone interested in Sealion or in the history special operations forces.




Note: Britain’s Secret Defences is also available in e-editions.


StrategyPage reviews are published in cooperation with The New York Military Affairs Symposium


Reviewer: A. A. Nofi   

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