
On this day in 1917, a note was handed to Walter Hines, American Ambassador to the UK. In it was the Zimmerman Telegram, a top-secret communication between German government officials that had been intercepted by British intelligence services. The telegram – sent by German Staatssekretär (civil servant) Arthur Zimmerman to his country’s embassy in Mexico – was an attempt to draw Mexico into WWI on Germany’s side. In the telegram, Zimmerman outlined the situation:
- Germany intended to begin unrestricted submarine warfare in the Atlantic against enemy commercial, military and pleasure vessels. The plan would, hopefully, bring England to its knees and force it out of the war.
- In the likely event that America declared war on Germany, Zimmerman invited Mexico to attack from the south and reclaim its lost territories: Texas, Arizona, and New Mexico.
- Zimmerman closed with a suggestion that the Mexicans align with Japan against American interests in the Pacific.

At that point, Germany’s greatest fear was the entrance of America into WWI. Mexico, however, was unable and unwilling to commit to the plan as it was embroiled in a civil war and already in conflict with the Americans on its border. Germany went ahead with its submarine campaign and sank a number of American ships. This, combined with public outrage at Zimmerman’s telegram, enabled American president Woodrow Wilson to ask Congress for “a war to end all wars” in April of 1917. His wish was granted (despite loud complaints from American the anti-war movement) and soon, American “doughboys” (infantrymen) were headed for France.

Although the European belligerents were running out of steam by 1917 and America did not single-handedly win the conflict, the entrance of a fresh, new power into the war undoubtedly tipped the balance in the Allied favour. Although the defeat of Germany and the Central Powers in 1918 was a result of many factors, the ill-advised Zimmerman Telegram was one of the most significant events in bringing the Americans into the war.