35 notable events from 1866 — wars, murders and rail accidents.
- Battle of Callao
May 2, 1866 · Peru · War & armed conflict
- Fenian raids
Apr 1866–Oct 1871 · Canada · War & armed conflict
- Fetterman Fight
Dec 21, 1866 · United States · War & armed conflict
- General Sherman incident
Sep 5, 1866 · North Korea · War & armed conflict
- Memphis massacre of 1866
May 3, 1866 · United States · Riot & unrest
- French expedition to Korea
Oct 1866–Nov 1866 · South Korea · War & armed conflict
- Battle of Curupayty
Sep 22, 1866 · Argentina · War & armed conflict
- New Orleans Massacre of 1866
Jul 30, 1866 · United States · Massacre
- Teradaya incident
Mar 9, 1866 · Japan · Murder & homicide
- Cretan revolt (1866–1869)
Aug 21, 1866–Jan 20, 1869 · Greece · Riot & unrest
- Baikal Insurrection
Jun 1866 · Russian Federation · War & armed conflict
- Bombardment of Valparaíso
Mar 31, 1866 · Chile · Bombing & explosion
- Catholic Persecution of 1866
1866–1871 · Massacre
- Oaks explosion
Dec 12, 1866 · United Kingdom · Industrial & structural disaster
- Panic of 1866
1866 · Crisis
- Seven and a Half Days Revolt
Sep 22, 1866 · Italy · War & armed conflict
- Sanjō Seisatsu Incident
Oct 20, 1866 · Japan · Incident
- Circleville Massacre
Apr 21, 1866 · United States · Genocide & ethnic violence
- Maungatapu murders
Jun 12, 1866 · New Zealand · Murder & homicide
- Kurashiki Asao Disturbance
1866 · Japan · War & armed conflict
- Teishin nijunikai-kyo ressha incident
Oct 8, 1866 · Japan
- Welwyn Tunnel rail crash
Jun 9, 1866 · United Kingdom · Rail accident
- Abkhazia uprising (1866)
Sep 1, 1866 · Georgia · War & armed conflict
- Richard Burgess (murderer)
Jun 13, 1866 · Murder & homicide
- Action of 22 August 1866
Aug 22, 1866 · Portugal · Natural disaster
- 1867 Macedonian rebellion
1866–1867 · North Macedonia · War & armed conflict
- Franois rail disaster
Dec 23, 1866 · France · Rail accident
- 1866 Bingöl earthquake
May 12, 1866 · Türkiye · Earthquake
- Johnstown, Pennsylvania platform collapse
Sep 14, 1866 · United States · Disaster
- 1866 Gallatin County race riot
Aug 1, 1866 · United States · Riot & unrest
- Separatist movement in Iași, April 15, 1866
Apr 3, 1866 · Romania · War & armed conflict
- Uprising in the Kaitago-Tabasaran District (1866)
Jul 1, 1866 · Russian Federation · War & armed conflict
- 1866 Poznań cholera epidemic
Oct 22, 1866 · Poland · Epidemic & disease
- Daimiel train collision
Dec 9, 1866 · Spain · Rail accident
- 1866 Colon explosion
Apr 3, 1866 · Bombing & explosion