- United States enters World War I.
- Russian Revolution overthrows the czars. Beginning of Russian civil war.
- Finland declared its independence on December 6 1917.
- Lions Clubs International was formed.
- Physics Charles Glover Barkla
- Chemistry - not awarded
- Medicine - not awarded
- Literature - Karl Adolph Gjellerup, Henrik Pontoppidan
- Peace - International Red Cross, Geneva.