It is now known as "Veterans' Day" in the United States, but originally November 11th was "Armistice Day." It marked the end of the Great War, or what, with the benefit of tragic hindsight, came to be called the First World War.
On April 6, 1917, the United States entered a European war that had long been stalemated along the Western Front. In the Senate, the vote for war was 82-6; in the House, 373-50.
At first, the American contribution was limited primarily to naval forces and war materiel. Before military conscription began in the summer of 1917, the United States' Army, with only 130,000 men, was smaller than Belgium's. Before the war ended, however, the United States would have 4.8 million men under arms.
It was not only the American military contribution that turned the tide in the war. On January 8, 1918, President Wilson announced his Fourteen Points, a set of war aims designed to convince the German people, if not their stubborn leadership, that peace might be more palatable than a continuation of the war and its privations. That the Fourteen Points were generally acceptable to Germany was demonstrated by a "prearmistice agreement" under which the Germans, the Allies, and the Americans all agreed to make the Fourteen Points the foundation for the ultimate peace agreement.
On September 29, 1918, General Ludendorff informed the German government that Germany's military situation in northern France had become untenable. The German government communicated its desire for peace to President Wilson, but Wilson insisted that he would only negotiate with a democratic Germany. When his military withdrew its support, Kaiser Wilhelm was forced to abdicate the throne and Wilson's condition for a democratic negotiating partner was satisfied. Meanwhile, to pressure the Allies to make peace on the basis of the Fourteen Points, Colonel House hinted that the United States might negotiate a separate peace with Germany. With modest reservations regarding the Fourteen Points, the Allies agreed to accept Germany's overtures for peace.
On November 8, Germany sent its representatives to northern France. There, in the Compiegne Forest aboard Marshal Foch's railroad car, an armistice was signed at 5:00 a.m. on November 11. It took effect six hours later.
The guns fell silent along the Western Front on the eleventh hour of the eleventh day of the eleventh month in 1918.