“They begged me to turn all my efforts to the unraveling of Japanese secrets, and I, in a moment of enthusiasm, had promised them either a solution or my resignation within a year. I had before me about hundred Japanese diplomatic code messages from and to different Japanese posts throughout the world.” (Herbert O. Yardley in, The American Black Chamber, p.251)

A Deceiving Patriot: Breaking Japanese Codes

The American Black Chamber’s greatest accomplishment was the decoding of Japanese secret codes. By July 1919, The American Black Chamber was all set up in their townhouse, and had begun the work to aid the United States. However, while the American Black Chamber was settling down in New York City, anti-Japanese feelings were rising throughout the world, and most prominently, in the United States. In his novel, Yardley explains one of the reasons for such tensions. "The reader will recall that back in 1919 there was a great of anti-Japanese feeling throughout the world. The American people were especially concerned because Japan has brought up the question of race equality at the Peace Conference…Aside from this we feared the Anglo-Japanese Alliance which was still in effect.” (Page 250.)

With the tumultuous relation the U.S had with Japan at the moment, the new elected director at the time, a General E. Nolan, requested that Yardley and his team solve Japanese diplomatic codes.  Since Yardley was confident in his team’s skills, he promised Director Nolan a solution within a month. However, upholding that promise would be a hard task to fulfill for  Yardley had underestimated the difficulty of Japanese codes. With its unique vocabulary and grammar in both its written and spoken forms, Japanese is most definitely one of the most complex languages.

Month’s into his attempts to decipher the Japanese codes, Yardley grew exhausted, and begun to seek comfort and strength from his wife and fellow cryptographer, Edna Ramsaier. 

“She never asked any questions and listened in silence to my long stories of failure while prepared me something to eat. And while I ate, and drank quantities of black coffee for I could not sleep without it, I told her, over and over again, that I would never succeed.” (Page 265.)​​

Ultimately , Yardley  deciphered the Japanese codes,and by February 1920, Yardley sent the first translations of Japanese decipherments to Washington, with the help of a Japanese missionary that translated the decipherments. However,  this would be his last achievement for after it, his attention  started turning elsewhere, primarily his own private endeavors.

Routine Technique

Until 1921, the American Black Chamber relied on the Japanese’ routine manner of composing telegrams since it gave them hints of word or phrases that they should be looking for. This technique facilitated their task when they had to identify groups in a new code. However, this method became problematic when the Japanese changed their codes, causing the American Black Chamber to also develop a new technique of encipherment.

As a reward for decoding the Japanese cipher, the American Black Chamber’s resources were expanded and its headquarters, relocated.  The lease to their first headquarters in the brownstone was sold in 1920 and they moved a short distance to another brownstone between and Lexington and Third Avenues at 141 East 37th street, on July 1, 1920.