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.

Read more
Hints: View this page full screen. Skip to the next and previous photo by typing j/k or ←/→.

Most Recent

  • Ng Han Guan / AP

    Riot Police Lay Siege to Hong Kong University Occupied by Protesters

    Some of the most violent clashes so far of the five-month-old pro-democracy protest movement in Hong Kong took place this past weekend, as riot police stormed the campus of a university where protesters had barricaded themselves.

  • Ivan Alvarado / Reuters

    Photos of the Week: Prehistoric Tongue, First Snow, Panda Scan

    Autumn colors in Belgium; chess-boxing in Paris; dinosaurs in India; bushfires in Australia; impeachment hearings in Washington, D.C.; Santa Claus in Germany; tennis in London, and much more

  • NASA

    The Flight of Apollo 12: Photos From 50 Years Ago

    A look back at the second mission to land humans on the moon, which blasted off on November 14, 1969.

  • Stefano Mazzola / Awakening / Getty

    Venice Underwater: The Highest Tide in 50 Years

    A record-setting acqua alta has left much of Venice submerged, following stormy conditions blowing in from the Adriatic Sea.