100 Years Ago, the United States Entered World War I

On April 6, 1917, the United States congress voted to formally enter World War I. More than two years of war had been waged in Europe, as the U.S. tried to remain neutral. In early 1917, German submarine attacks on all ships bound for England resumed, adding to the building pressure to join the war against the German Empire and the Central Powers, which led President Woodrow Wilson to ask Congress to declare war. I’ve covered World War I extensively before, in the 10-part series World War I in Photos. Today, a collection of relatively-unseen images from a century ago, focusing on American war involvement, some on the home front, some overseas, and some images of their allies and enemies as well.

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