Samurai and Secret Communication?

Hi all, I'm new around here and have a question maybe someone can help
me with.

David Kahn's book "The Codebreakers" deals with the history of codes,
ciphers and cryptanalysis. Most of the book deals with Europe---from
Caesar ciphers to the European black chambers. Japan only gets
mentioned toward the end---WWII of course.

Now most people with an interest in Japan know about the Allied
efforts to decipher and read Japanese codes in WWII.

But what about earlier? Did the samurai (daimyo mostly i would assume)
use any sort of secret writing? Did their messangers just carry
plaintext documents? If so, were there any cases of intercepted
messages affecting strategy or even individual battles?

I know the Church was using codes / ciphers in the 1500's, so I would
image that the missionaries in Japan would have at least known the
basics of cryptography. (Especially the Jesuits). Maybe they taught
some to a few daimyo?

I've done a little bit of research but haven't been able to find much.
Any one know of any good sources for this topic?

yoroshiku

--
Osugi Sakae
www.openhistory.org

Chris Spackman wrote:

>
>
> I know the Church was using codes / ciphers in the 1500's, so I would
> image that the missionaries in Japan would have at least known the
> basics of cryptography. (Especially the Jesuits). Maybe they taught
> some to a few daimyo?
>
> I've done a little bit of research but haven't been able to find much.
> Any one know of any good sources for this topic?
>
> yoroshiku
>

I know of no good sources, there are stories about Date Masamune, whose
secret letters were captured and used by Hideyoshi to accuse him of
wrongdoing and he avoided punishment by pointing out that his "secret"
signature was not on the letter. This scene is retold and replayed in novels
and movies by various characters. The message itself was plaintext if I
recall.
The Takeda used smoke signals to move info across large distances in a
hurry, surely they had codes for this. The info you seek may not be in ONE
book but in books on specific han Lords and or battles.
pray for surf,
Tom

slowest reply in the west....

Hello all...
I train with the Genbukan Ninpo Bugei and have seen a book by my Grandmaster
Tanemura Shoto Sensei in which he describes various methods of 'Aizu' and
'Ango' Jutsu...signalling techniques that have been handed down from around
the 15th century
"Aizu are ways of making secret signals, such as using smoke, a mirror or
other shiny metal object, flags, coloured rice, or noise such as from a shell
horn (Conch, presumably), hand held drum, large drum or bell."
Ninpo secrets-Tanemura Shoto
It is also in the book that the Shinobi agents from the 'Iga' region (in Mie
prefecture) used written codes 'Ango' that they called the 'shinobi iroha'
commonly using basic Kanji (chinese characters) as left radicals and colours
as right radicals and combining them in such a way as to form the Japanese
'Kana' (type of sound alphabet) to form words with.
There are also various other methods using Kana and Kanji but the essentials
are there...The Kenshin ryu used a method known as 'Shichiji no Kana' with
seven (Hira) kana along the top row to form a sentance that was predetermined
and a further seven kana running down the page in another sentance...If the
agent knew the beginning phrases the Hiragana characters were placed in to
the field and looking at the combinations he could decipher the code.
These are only basic methods and very similar to modern code structures but
a little experimentation could allow practically any code to be set up using
these methods.
As mentioned the Takeda clan used large signalling fires that were placed
upon long (pivoted) sticks that were raised by a few men to signal groups
further down the battle lines. The Takeda network of fires was
immense...apparently covering southern Shinano, Kai and the surrounding
province borders. Ithink their methods and strategys are contained in 'Heiho
Okugisho' by Yamamoto Kansuke..a legendary retainer of Shingen ko.
Hope this waffle helps you out....

--- In samuraihistory@y..., fifthchamber@a... wrote:

> Hello all...

[snip]

> Ninpo secrets-Tanemura Shoto

[snip]

> Heiho Okugisho by Yamamoto Kansuke

[snip]

> Hope this waffle helps you out....

Yes, it does. Thanks a lot. I'll try to find those books right away.
They sound very promising.
--
Chris

--- In samuraihistory@y..., TOM HELM wrote:

>
> I know of no good sources, there are stories about Date Masamune,

whose

> secret letters were captured and used by Hideyoshi to accuse him of
> wrongdoing and he avoided punishment by pointing out that his

"secret"

> signature was not on the letter. This scene is retold and replayed

in novels

> and movies by various characters. The message itself was plaintext

if I

> recall.
> The Takeda used smoke signals to move info across large

distances in a

> hurry, surely they had codes for this. The info you seek may not be

in ONE

> book but in books on specific han Lords and or battles.
> pray for surf,
> Tom
>
> slowest reply in the west....

Thanks, I'll look into Date Masamune. I was beginning to fear that
samurai / daimyo never used code.

Maybe Japanese use of codes may be more appropriate to the
Meiji Restoration or the Sino-Japanese war, possible even the
Russo-Japanese war.

--
Chris

>
>
> Maybe Japanese use of codes may be more appropriate to the
> Meiji Restoration or the Sino-Japanese war, possible even the
> Russo-Japanese war.
>
> --
> Chris
>

YES! Much more likely then as they would definitely be under the influence
of European military practice. I am sure the info on earlier periods is out
there, good hunting.
T