March 6 - Finnish Air Force founded. The blue swastika is adopted as its symbol as a tribute to the Swedish explorer and aviator Eric von Rosen who donated the first plane. Von Rosen had painted the buddhist symbol on the plane as his personal lucky insignia.
March 7 - World War I: Finland forms an alliance with Germany.
August - "Spanish Flu" Influenza becomes pandemic; over twenty-five million people die in the following six months (three times as many as died during the war).
August 8 - World War I: Battle of Amiens - Canadian troops, backed by Australians, begin a string of almost continuous victories with a push through the German front lines. German General Erich Ludendorff will later call this the "black day of the German army."
August 30 - Strike of 20,000 London policemen with demands of increased pay and union recognition.
October 8 - World War I - In the Argonne Forest in France, US Corporal Alvin C. York almost single-handedly kills 25 German soldiers and captures 132.