United States in World War I

United States in World War I
1917–1918
American troops advancing on the Western Front, March 1918.
Location	United States
President(s)	Woodrow Wilson
Key events	Selective Service Act of 1917 Food and Fuel Control Act Conscription
Chronology Progressive Era Roaring Twenties

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The United States became directly involved in World War I after declaring war on Germany on April 6, 1917. The declaration ended nearly three years of American neutrality in the war since the beginning, and the country's involvement in the conflict lasted for nineteen months before a ceasefire and armistice were declared on November 11, 1918. The U.S. played a major role in providing much needed supplies, raw material, and money to the United Kingdom, France, and the other Allied powers, even well before 1917.

After declaring war, the U.S. mobilized over 4.7 million military personnel. General of the Armies John Pershing, served as Commander of the American Expeditionary Force (AEF) in France, of which over 2 million American soldiers served. American troops began to arrive in Europe by June of 1917, first at a slow rate, but by the summer of 1918 the rate had skyrocketed to 10,000 soldiers arriving each day. Most of the ground fighting for the U.S. took place on the Western Front. At sea, the U.S. Navy would play a key role in the Allied convoy system and in the ongoing battle against German submarines. Over 116,000 American servicemen were lost in the war.^[1]

Although there was an initially slow start in mobilizing the armed forces, economy and labor force, by spring 1918, the nation was poised to play a role in the conflict. Under the leadership of President Woodrow Wilson, the war saw a dramatic expansion of the United States government in an attempt to harness the war effort and to significantly increase in the size of the U.S. Armed Forces. The war also represented the climax of the Progressive Era, as it sought to bring reform and democracy to the world.