World War 1 ushered out with the signing of the Treaty of Versailles. However, fighting ceased on November 11, 1918 when armistice, marked an end to hostilities between the allied nations and Germany. Which went into effect on the eleventh hour of the eleventh day of the eleventh month, which was referred to as Armistice Day.
It was not until November 11, 1919, when President Wilson proclaimed it as the first commemoration day. Having the original expectations of the day to be observed with parades and public meetings and a brief suspension of business beginning at 11:00 a.m.
However it did not become a legal holiday until May 13, 1938. A day to be recognized as the cause of world peace. Which was primarily set aside to honor the veterans of World War 1. It was not until after World War 2 when on June 1, 1954 after Congress amended the change of Armistice to Veteran. Making November 11th became a day to honor American veterans of all wars.