- May 4 23rd Kentucky Derby: Buttons Garner aboard Typhoon II wins in 2:12.5
- May 4 Fire in Paris bazaar at Rue Jean Goujon kills 200
- May 8 22nd Preakness: T Thorpe aboard Paul Kauvar wins in 1:51ΒΌ
- May 11 Washington Senator catcher Charlie Farrell throws out 8 attempted stealers
- May 12 1800-1900 year old fossil of "girl of Yde" found in Drente, Netherlands
- May 12 Battle at Thessalie: Turkish army beats Greece
- May 14 Great Britain signs treaty with Emperor Menelik II of Abyssinia
- May 15 The Greek army retreats with heavy losses in the Greco-Turkish War.
Event of Interest
May 15 The Scientific-Humanitarian Committee is founded in Berlin by Magnus Hirschfeld, the first-ever LGBT rights organization
Magnus Hirschfeld
Event of Interest
May 17 The first successful submarine that can run submerged for any considerable distance and combines electric and gasoline engines is launched in the USA by its designer John Philip Holland
John Philip Holland
Historic Publication
May 18 "Dracula" by Irish author Bram Stoker is published by Archibald Constable and Company in London
Bram Stoker
Event of Interest
May 18 Herbert Henry Dow founds Dow Chemical in Midland, Michigan
Herbert Henry Dow
Event of Interest
May 19 Oscar Wilde is released from Reading Gaol
Oscar Wilde
- May 20 British Open Golf, Royal Liverpool GC: English amateur Harold Hilton wins 2nd Open title by 1 stroke from Scot James Braid
- May 21 Yerkes Observatory 40" (1m) refractor used for 1st time
- May 22 The Blackwall Tunnel, London, under the River Thames is officially opened
- May 29 31st Belmont: J Scherrer aboard Scottish Cheiftain wins in 2:23.25