- May 5 The British and Foreign Society for Improving the Embossed Literature of the Blind adopts Braille as best format for blind people
- May 10 Jem Mace & defends his heavyweight crown against Irish champ Joe Coburn, it lasts 1 hr & 17 minutes, & neither is struck by a punch
- May 12 Royal assent passes Manitoba Act of 1870, approving Manitoba becoming a province of Canada
- May 20 Second Chamber of the Dutch Parliament abolishes capital punishment in The Netherlands
- May 24 Memoria of Jackson Kemper, 1st Missionary Bishop in US
- May 25 Irish Fenians raid Eccles Hill, Quebec
- May 31 Congress passes 1st Enforcement Act (rights of blacks)
- May 31 E. J. DeSemdt patents asphalt pavement
Authors
Dictators
Explorers
Outlaws
Queens
Spies