Naval Warfare Books

Book reviews

Action This Day

Smith, Michael and Erskine, Ralph

2001, Bantam Press
ISBN 0593049101
Hardcover, 543 pages, 26 b&w photos, several figures, diagrams, and facsimiles

Type. Collection of articles by various authors
Pros. Wide range of topics; personal accounts of Bletchley workers
Cons. None to mention

This is a very interesting collection of 22 articles, each preceded by an introduction by the editors, on various topics concerning the "best-kept secret in modern British history", the signals intelligence work carried out by 10,000 codebreakers and analysts at Bletchley Park during World War II. The title refers to a memo by Churchill ordering that Bletchley’s codebreakers be provided with everything they needed; before this turning point, operations had suffered from simple lack of staff and equipment, to the extent that, in October 1941, four of the leading codebreakers at Bletchley (Turing, Welchman, Alexander, and Milner-Barry) sent a letter direct to Churchill describing their plight and warning of its consequences if left unchanged. The text of the letter and the memo received in response are reproduced in full in this volume.

In addition to fascinating first-person accounts from Bletchley Park workers involved in World War II and postwar codebreaking (some sharing their stories for the first time here), the volume includes technical accounts of the breaking of specific codes, and also touches on various other topics, such as the development of Colossus (the first electronic digital computer), and codebreaking during the Cold War. Chapters specific to the U-boat war include Chapter 10: Breaking German Naval Enigma on Both Sides of the Atlantic, and Chapter 19: Enigma’s Security: What the Germans Really Knew, both by Ralph Erskine; and Chapter 11: Hut 8 from the Inside, by Rolf Noskwith.

The volume includes a glossary, index, notes and references, biographical notes on contributors, and four appendices: Appendix I: The very simple cipher which 'Snow', the first Double Cross agent, was given by his German controllers; Appendix II: Wehrmacht Enigma Indicating Systems, except the Kriegsmarine’s Kenngruppenbuch System; Appendix III: The Naval Enigma Kenngruppenbuch Indicator System - used with the main wartime ciphers; and Appendix IV: Cillies.

This is not a history of Enigma or codebreaking. While the chapters are arranged in a rough chronological order, and the editorial prefaces place each chapter in perspective, newcomers to the subject might want to start off with a book such as Seizing the Enigma or our own pages on this topic, to ensure they will get the most out of Action This Day. Those with a basic background knowledge of Bletchley Park’s work will welcome this series of penetrating illuminations into specific facets of that work, and the personalities who achieved it.

This book was published in October, 2001 as part of a sixtieth anniversary commemoration of the "Action This Day" memo which established Bletchley Park as Britain’s codebreaking center. The commemoration also included a series of lectures at the Royal United Services Institute in London; the chapters appearing in the book are actually edited versions of these lectures. All royalties from the book go to the Bletchley Park Trust.

This book was submitted to for review purposes.

Review written by Tonya Allen.

Published on 7 Jul 2002.

This title is highly recommended.

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