"An officer of the War Staff, preferably from the I.D., should be selected to study all the decoded intercepts, not only current but past, and to compare them continually with what actually took place in order to penetrate the German mind and movements. All these intercepts are to be written in a locked book with their decodes and all other copies are to be collected and burnt. All new messages are to be entered in the book and the book is only to be handled under instructions from the C.O.S.. The officer selected is for the present to do no other work. I should be obliged if Sir Alfred Ewing will associate himself continuously with this work."
Winston Churchill, in a letter that served as the unofficial charter of Room 40
Winston Churchill, in a letter that served as the unofficial charter of Room 40
Impact of Room 40
Room 40 was a British cryptoanalysis project that intercepted the Zimmermann Telegram and decoded it. They proceeded to send the message to the United States, and from there Woodrow Wilson released it to the press in the following months. The astounding amount of cryptographic work carried out by Room 40 resulted in a significant impact in the war, most important of which was the arrival of America. The documents decoded using the Signalbuch der Kaiserlichen Marine, a German codebook found in a naval wreck, provided a valuable insight into the operation of the Central Powers. ("The Charter of Room 40")Without the work of Room 40, the U.S may have remained neutral throughout the war.