Armistice Day is the anniversary of the symbolic end of World War I on 11 November 1918. It commemorates the armistice signed between the Allies and Germany at Rethondes, France, for the cessation of hostilities on the Western Front, which took effect at eleven o’clock in the morning — the “eleventh hour of the eleventh day of the eleventh month”. While this official date to mark the end of the war reflects the cease fire on the Western Front, hostilities continued in other regions, especially across the former Russian Empire and in parts of the old Ottoman Empire.
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The holiday is commonly printed as Veteran’s Day or Veterans’ Day in calendars and advertisements. While these spellings are grammatically acceptable, the United States government has declared that the attributive (no apostrophe) rather than the possessive case is the official spelling.