1921 — President Warren G. Harding proclaims November 11, Armistice Day, a national holiday. The first burial ceremony at the Tomb of the Unknown Soldier at Arlington National Cemetery, Va. is held.

Elsewhere that year:

• Georgia issues its first chiropractic license.
• The end of the wartime boom causes business depression and high unemployment. A National conference proposes a job program.
• The Ku Klux Klan promotes “white supremacy” and seeks to control politics in many southern communities.
• A Paris conference of the Allies establishes German reparation payments for damages during World War I. German liability is set at about $33 billion.
• DeWitt Wallace, publisher, founds Reader’s Digest.
• John Larson, a psychiatrist, invents the polygraph, or lie detector test.
• Hermann Rorschach, a Swiss psychiatrist, publishes Psychodiagnostics, in which he introduces his famous inkblot test for the study of personality.