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The Emperor's Codes: The Breaking of Japan's Secret Ciphers
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The Emperor's Codes: The Breaking of Japan's Secret Ciphers

3.58  ·  Rating details ·  165 ratings  ·  24 reviews
In this gripping, previously untold story from World War II, Michael Smith examines how a group of eccentric codebreakers cracked Japan's secret codes and turned the tide of the war in the Pacific. Drawing upon recently declassified British files, privileged access to Australian secret official histories, and interviews with many of the men involved, The Emperor's Codes ta ...more
Paperback, 368 pages
Published November 5th 2002 by Penguin Books (first published 2000)
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Nov 16, 2017 rated it liked it
This book is a little outside my comfort zone. Not because of the subject matter, which I found intriguing, but due to the fact that the actual workings of decryption involve a lot of math that is outside my ability to follow along. The author goes over a 'simple' example of working a code and by the third line of working the problem I am completely lost and just nodding along and thinking to myself I will take your word for it.

Fortunately enough for yours truly that didn't happen very often. T
Jul 01, 2018 rated it really liked it
The Emperor's codes goes into great detail about all of the code breaking efforts on the part of the British and Americans during WWII. It is focused primarily on the Pacific Theater and the many different sets of codes used for diplomats, navy, air to ship, air to air, and others. It does also touch on activities to break the Nazi Enigma codes. Mostly a very fascinating read but what I found frustrating was keeping up with the myriad names of the participants in England, America, Philippines, I ...more
Dec 02, 2018 rated it liked it
This book is by a Brit and focuses on their efforts to crack the Japanese WWII codes. He is trying to redress the notion that the code breaking was largely an American effort. He spends a lot of time emphasizing how amateurish the initial American efforts were, and how the U.S. navy cryptanalysts were uncooperative with the Brits and Australians. This may all be true but the subsequent British leaks to the Soviets may support a sense that this was not entirely unwarranted. He rather grudgingly a ...more
Mar 05, 2018 rated it really liked it  ·  review of another edition
This book, especially read after "Battle of Wits" (and multiple reading of Kahn's The Codebreakers) shed a entire new light on the codebreaking of the famous Japanese code called JN25 (a great part of the victory at Midway & killing of Yamamoto came from the breaking of that code).

Nowhere before did I see mention of the immense work done at Bletchley Park, including the fact that Tiltman broke JN25 way before the Americans did and they the multiple interception stations by the Brits provide
Neil Hunt
Interesting, but long

Fascinating story of breaking a wide range of codes used by the Japanese. There is a small section walking through the process of breaking the codes, describing aligning the groups by "additive", guessing common words to try out different additive values, validating with various other sources, and gradually building up the underlying code books.

The collaboration, or lack of collaboration, between Britain and the US Is a major theme.

The book uses the device of lengthy quotes
Daniel Q
Jul 11, 2017 rated it really liked it  ·  review of another edition
This is a good account of the efforts by England (and allies) to gather information from Japan's encoded communications in World War II. It is not very deep in technical information and does not cover the machine-based ciphers (that were broke by US), but gives a good idea of the real work involved. Forget the lone genius in the Hollywood movies that magically makes all communication readable in real time. This is a story involving thousands of people working really hard to obtain partial decode ...more
Thomas Kirk
Jan 07, 2019 rated it really liked it  ·  review of another edition
Great story

The story of the code breakers of WW-2 is fascinating because it sheds light on how the brilliance of a few people behind the scenes made field commanders look exceptional.

I didn't give the book a five star rating because there were large excerpts that dealt with the tedium of cracking Japanese codes and cyphers.

If you are interested in WW-2 then read this book.
Andrew Scholes
Dec 06, 2018 rated it really liked it  ·  review of another edition
t was well written and not too technical. I had read another book that really got into excruciating detail of codes and how they were translated and pages upon pages of code. I found it interesting how close to the vest each of the allied code breaker services held their information. For much of the war they did not and would nto share information of codes that were broken or clues they found to break the codes.
Kevin Reeder
Packed with knowledge about WWII code breakers

Interesting historical pice about how we won the war by breaking the coded messages. Fascinating information I never knew. Good read.
John G
Jun 14, 2018 rated it really liked it  ·  review of another edition
Much to be learned

A very readable book on the important part that codebreaking played in the Pacific theater in WW2. It is good to learn how all this came about.
Mark Maddrey
I found this to be a decently informative overview of the Allied code breaking effort on the Japanese codes, but I could not help feeling like something was missing. The book never came alive for me in the way that creative non-fiction books by writers such as Erik Larson, Steven Johnson, or Simon Winchester do. I felt like I was reading a school paper that went through everything that happened in order. Everything was there but it was inert. I also felt like the author's stated opinion that the ...more
May 14, 2014 rated it liked it  ·  review of another edition
Shelves: 2013, history, wwii
The story of the breaking of Germany's codes on WWII is fairly well known - there have been many books written and both films and tv documentaries made, but less attention has been paid to the story of intelligence operations and codebreaking in the Pacific theatre. This is not unexpected as in the UK we do seem to focus more on the war in Europe.

Because of this unfamiliarity I did find this book informative, it was a rather dense read though and I felt a bit more of an overview would have helpe
Nishant Pappireddi
This book was a great account of how many Japanese codes were broken, with particular emphasis on British and Australian codebreaking efforts, though the American contributions are still explained.
The German Enimga cipher and the quest to break it is one of WW II's most intriguing stories, however, similar efforts to break the Japanese codes in the Pacific theater were no less crucial or difficult.
This book is a little too dense and difficult to get through, even for someone like me who is passionate about military history. It is detailed, but too detailed. I might have studied it if I had been a student of military history, but certainly difficult to push through if attempting to read f
Jul 04, 2014 rated it liked it
Shelves: ww2
I thought the book was good, there are much better code books. I was interested in this one, because it was the first book I saw that dealt with Japanese codes during ww2.

The book was more about how American code breaking was just as good or better than Alan Turing and British code breaking abilities, which is false.

Also I thought the book lacked in overall code breaking and providing examples of how they broke codes, seemed more like a history of it not actual code breaking.
David R.
Sep 02, 2016 rated it liked it
A thoroughly interesting account of the work and setbacks behind the effort to crack the Japanese military codes in the WW2 Pacific Theater, from the perspective of the British armed forces. It suffers from some organizational issues as well as an unnecessary degree of Anti Americanism.
Mar 02, 2009 rated it liked it
great drama. gets into all the tension behind the UK and US code breakers. and filled with interesting facts--- did you know many of the US Military codes breaks took amphetamines to keep working and stay sharp.
Ian Chapman
Nov 03, 2015 rated it really liked it
Interesting account of Allied efforts against Japanese codes, with some rightful highlighting of the Australian contribution.
Jul 09, 2010 added it
here's a Goodreads challenge - how many can own up to reading two different books by the same name? gotta go get lotto tickets.....
Terry Graap
Feb 06, 2015 rated it it was amazing
The Americans, English, Australians, and Canadians' codebreakers helped turn the tide in the WWII in the Pacific against Japanese.
Yoshiki Komi
Jul 31, 2015 rated it it was ok
Very few technical explanation. Most of parts are the life of code breakers or historical events during WW2.
Christopher Telcontar
Jul 30, 2015 rated it did not like it
Shelves: ww2
Half the book was padded with anecdotes about life at Bletchley Park or the food in Colombo and such. The early material leading up to PH was interesting; little after that.
Aug 15, 2014 rated it really liked it  ·  review of another edition
Excellent account of the lives of people involved in breaking the Japanese military codes of WWII. Not to much on the technical side of cryptanalysis although there are some brief descriptions.
Jun 11, 2012 rated it liked it
Shelves: world-war-ii
Mostly an oral history from individuals who were involved in Britain's lesser-known code-cracking efforts.
rated it really liked it
Dec 31, 2014
Brian Thrall
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Nov 30, 2014
Mark J Greene
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Sep 08, 2013
Kathleen Foskett
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Jun 07, 2011
rated it it was ok
Sep 09, 2009
John somers
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Jul 28, 2011
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There is more than one Michael Smith in the database.

Michael Smith is a British author and screenwriter who specializes in spies and espionage.

Source: Wikipedia.