|Centuries:||19th century – 20th century – 21st century|
|Decades:||1880s 1890s 1900s – 1910s – 1920s 1930s 1940s|
|Years:||1913 1914 1915 – 1916 – 1917 1918 1919|
- January 1 – The Royal Army Medical Corps first successful blood transfusionblood that had been stored and cooled.
- January 1 – Impressionist painter Monet paints 'Water Lilies'.
- January 5 – Heavy rain – allegedly caused by rainmaker Charles Hatfield – begins; it will cause flooding around San Diego, California
- January 8 – Allied forces withdraw from Gallipoli
- January 13/14 – A heavy storm sweeps through the Zuiderzee in the Netherlands, causing extensive damage. This storm helped the Dutch parliament to decide to build the Afsluitdijk and build polders in the current IJsselmeer.
- January 17 – The Professional Golfers Association of America (PGA) is formed
- January 18 – A 611 gram chondrite type meteorite struck a house near Baxter, Stone County, Missouri.
- January 23 to January 24 In Browning, Montana, the temperature drops from +6.7 °C to -48.8 °C (44 °F to -56 °F) in one day, the greatest change ever on record for a 24-hour period.
- January 24 – In Brushaber v. Union Pacific Railroad the Supreme Court of the United States upholds the federal income tax
- January 28 – Louis D. Brandeis becomes the first Jew appointed to the Supreme Court of the United States.
- January 29 – World War I: Paris is bombed by German zeppelins for the first time.
- February 3 – Parliament buildings in Ottawa, Canada are burned down.
- February 9 – 6.00 PM – Tristan Tzara "founds" Dadaism (according to Hans Arp)
- February 11 – Emma Goldman is arrested for lecturing on birth control.
- February 11 – Baltimore Symphony Orchestra presents its first concert
- February 21 – World War I: In France the Battle of Verdun begins.
- March 20 – Albert Einstein publishes his Theory of Relativity, which explains the relationship between mass and energy.