The Zimmermann Telegram

U.S. National Archives and Records Administration , Wikipedia

The Zimmermann Telegram was a coded telegram dispatched by the Foreign Secretary of the German Empire, Arthur Zimmermann, on January 16, 1917, to the German ambassador in Mexico, Heinrich von Eckardt, at the height of World War I.

The telegram instructed the ambassador to approach the Mexican government with a proposal to form a military alliance against the United States. It was intercepted and decoded by the British, and its contents hastened the entry of the United States into World War I.
 

The Zimmermann telegram as it was sent from Washington to Mexico

The telegram, completely decrypted and translated.

Telegram

Zimmermann's message was

On the first of February, we intend to begin unrestricted submarine warfare. In spite of this, it is our intention to endeavour to keep the United States of America neutral.

In the event of this not succeeding, we propose an alliance on the following basis with Mexico: That we shall make war together and make peace together. We shall give generous financial support, and an understanding on our part that Mexico is to reconquer the lost territory in New Mexico, Texas, and Arizona. The details of settlement are left to you.

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, on his own initiative, invite Japan to immediate adherence with this plan; at the same time, offer to mediate between Japan and ourselves.

Please call to the attention of the President that the ruthless employment of our submarines now offers the prospect of compelling England to make peace in a few months.

Mexican response

A general assigned by Mexican President Venustiano Carranza assessed the feasibility of a Mexican takeover of their former provinces and came to the conclusion that it would not be possible or even desirable for the following reasons:
 

  • Attempting to re-take their former provinces would have meant certain war with the more powerful U.S.
  • No matter how "generous" it was, Germany's "financial support" would have been worthless because Mexico would have been in no position to use it to acquire arms and other military hardware, or ammunition and other war supplies since the U.S. was the only sizable arms manufacturer in the Americas. The Royal Navy controlled the Atlantic sea lanes, thus Germany would not possibly have had the capability to supply any quantity of what would have been needed for seizure and defence of the territory.
  • Even if Mexico had the military means to re-take the territory she would have had severe difficulty accommodating and/or pacifying the large English-speaking population.

    • Carranza formally declined Zimmermann's proposals on April 14, by which time the U.S. had declared war on Germany.