In early 1917, the nations of Europe had been involved in the conflict known as World War One for almost three years -- ever since the assasination of Archduke Franz Ferdinand by Gavrilo Princip, a Serbian nationalist. The fight, though, had yet to cross the Atlantic. The United States stayed neutral, and many Americans hoped it would remain so. However, it soon became obvious this was not meant to be.
In January of 1917, two British cryptographers -- Nigel de Gray and Reverand William Montgomery -- deciphered a telegram sent from German Foreign Minister Arthur Zimmermann to Count von Bernstoff, the German ambassador in Washington. The telegram had two purposes -- the first part informed the ambassador of Germany's decision to begin unrestricted submarine warfare. The second part, on the other hand, was supposed to be forwarded to the German Minister to Mexico, Heinrich von Eckhardt, instructing him to propose an alliance between Germany and Mexico.
In whole, the message read:.
Berlin, January 19, 1917 .
On the first of February we intend to begin submarine warfare unrestricted. In spite of this, it is our intention to endeavor to keep neutral the United States of America. .
If this attempt is not successful, we propose an alliance on the following basis with Mexico: That we shall make war together and together make peace. We shall give general financial support, and it is understood that Mexico is to reconquer the lost territory in New Mexico, Texas, and Arizona. The details are left to you for settlement. .
You are instructed to inform the President of Mexico of the above in the greatest confidence as soon as it is certain that there will be an outbreak of war with the United States and suggest that the President of Mexico, on his own initiative, should communicate with Japan suggesting adherence at once to this plan; at the same time, offer to mediate between Germany and Japan. .
Please call to the attention of the President of Mexico that the employment of ruthless submarine warfare now promises to compel England to make peace in a few months.
