Here’s some of what va.gov says:
“World War I – known at the time as “The Great War” - officially ended when the Treaty of Versailles was signed on June 28, 1919, in the Palace of Versailles outside the town of Versailles, France. However, fighting ceased seven months earlier when an armistice, or temporary cessation of hostilities, between the Allied nations and Germany went into effect on the eleventh hour of the eleventh day of the eleventh month. For that reason, November 11, 1918, is generally regarded as the end of “the war to end all wars.
[There is a photo that I don’t know how to post. Underneath the photo it says this:
Soldiers of the 353rd Infantry near a church at Stenay, Meuse in France, wait for the end of hostilities. This photo was taken at 10:58 a.m., on November 11, 1918, two minutes before the armistice ending World War I went into effect.]
In November 1919, President Wilson proclaimed November 11 as the first commemoration of Armistice Day with the following words...
...The United States Congress officially recognized the end of World War I when it passed a concurrent resolution on June 4, 1926, with these words...’
https://www.va.gov/opa/vetsday/vetdayhistory.asp
Thanks for the link!