- 1500 Pedro Álvares Cabral is the first european to discover Brazil, landing near Monte Pascoal, claims it for Portugal
- 1915 1st military use of poison gas (chlorine, by Germany) in WW I
- 1976 Barbara Walters becomes 1st female nightly network news anchor (Today Show)
- 1993 Holocaust Memorial Museum dedicated in Washington, D.C.
- 1994 7,000 Tutsi slaughtered by Hutus in the stadium at Kibuye, Rwanda
- 2006 243 people are injured in pro-democracy protest in Nepal after Nepali security forces open fire on protesters against King Gyanendra.
- 2016 Paris Agreement on climate change signed in New York binding 195 nations to an increase in the global average temperature to less than 2°C above pre-industrial levels and to pursue efforts to limit the increase to 1.5°C