• Archduke Francis Ferdinand is assassinated.

  • Austria-Hungary declares war on Serbia, beginning World War I.

  • Allied forces halt German advance into France during First Battle of the Marne.

    Allied forces halt German advance into France during First Battle of the Marne.
  • German submarine sinks the passenger liner Lusitania

    During crossing from New York to Liverpool, England, killing 128 Americans.
  • Battle of Verdun ends

    Battle of Verdun ends
    with 550,000 French and 450,000 German casualties.
  • The United States declares war on Germany.

  • President Woodrow Wilson presents to Congress his outline of Fourteen Points required for peace.

  • United States forces are victorious in the Battle of Cantigny, the first independent American operation.

    United States forces are victorious in the Battle of Cantigny, the first independent American operation.
  • Peace conference begins at Paris.

  • Draft of the covenant of the League of Nations is completed.

  • Treaty of Versailles takes effect.

  • United States signs separate peace treaties with Germany, Austria, and Hungary.