How Did The US Entered The First World War?

Great War or World War I was one of the deadliest conflicts in the history. This war lasted from 28 July 1914 to 11 November 1918. The war originated from Europe which results in the death of seven million civilians. Entry of US in the war was a very crucial point.  US President Woodrow Wilson, after a public opinion, declared US entry in Great War on April 2, 1917. There were several reasons for the US entry. This blog is about the major causes of why the US declared an attack on Germany and led to the victory of allies.

Unrestricted Submarine Warfare

President of United States declared neutrality of US towards the World war I in 1914. The UK was, however, the closest trading partner of America. When Germany announced unlimited warfare in Atlantic in Feb 1915 and attempted to sunk all the ships which enter the war zone of North Sea near Britain, tension start building between US and Germany. On May 7, 1915, Lusitania was attacked by Germans without any prior notice. There were 1,959 passengers on the ship out of which 1,198 were killed, including 128 Americans.

In August, Germany pledged to see to the safety of passengers before sinking unarmed vessels. But in November, Germany dropped an Italian liner without warning, killing 272 people, including 27 Americans. Public opinion in the United States began to turn irreversibly against Germany.

Read also: D-Day Of World War 2: Worst Days In The History Of Human Life

Zimmermann Telegram

British authorities gave the U.S. a copy of the “Zimmermann Note,” a coded telegram from German foreign secretary Arthur Zimmermann to the German ambassador to Mexico, Count Johann von Bernstorff. In the telegram, encrypted by British intelligence, Zimmermann stated that, in the event of war with the United States, Mexico should support Germany. In return, Germany promised Mexico to return the lost territories of Texas and New Mexico. On March 1, the U.S. State Department published the note, and American public opinion was united against Germany.

Below are the images of Zimmermann Telegram in encrypted and decrypted form.

Via –

Belgian Atrocities

Belgium was neutral from the very starting. On August 2, 1914, an ultimatum was sent to Belgium by Germany, demanding the passage to German troops to attack France. But Belgium wants to uphold their neutrality in war. So, On August 4, 1914, Germany invaded Belgium to attack France. They started their policy of terror against the Belgian civilians and burnt the towns and villages there. This incident in history is popularly known as Rape of Belgium. This is thought to be one of the reasons for the entry of US in Great War.


Establishment of democracy is also thought to be the reason behind the US entry. The US always wanted to establish the democracy in the world by eradicating the rule of empires. France and UK were democratic at that time. These were the primary reasons for which the US has to enter into the First World War.

“If either side does win such a victory it will probably mean the preparation of another war” By Woodrow Wilson in September 1914.

Read also: How Switzerland Managed To Remain Unconquerable During The World Wars?

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