|869 by topic|
|Ab urbe condita||1622|
|Balinese saka calendar||790–791|
|Chinese calendar||戊子年 (Earth Rat)|
3565 or 3505
— to —
己丑年 (Earth Ox)
3566 or 3506
|- Vikram Samvat||925–926|
|- Shaka Samvat||790–791|
|- Kali Yuga||3969–3970|
|Japanese calendar||Jōgan 11|
|Minguo calendar||1043 before ROC|
|Seleucid era||1180/1181 AG|
|Thai solar calendar||1411–1412|
995 or 614 or −158
— to —
996 or 615 or −157
- Summer – Emperor Basil I allies with the Frankish emperor Louis II against the Saracens. He sends a Byzantine fleet of 400 ships (according to the Annales Bertiniani), under the command of Admiral Niketas Ooryphas, to support Louis (who is besieging the city port of Bari), and to clear the Adriatic Sea of Muslim raiders.
- The Hagia Sophia Basilica (church) in Constantinople suffers great damage during an earthquake, which makes the eastern half-dome collapse. Basil I orders it to be repaired.
- August 8 – Lothair II, King of Middle Francia (Lotharingia), dies at Piacenza, on his way home from meeting Pope Adrian II at Rome, to get assent for a divorce. Lotharingia is subsequently divided between Lothair's uncles, Charles the Bald of France and Louis the German.
- The Danes, led by Viking chieftain Ivar the Boneless, 'make peace' with the Mercians (by accepting Danegeld). Ivar leaves Nottingham on horseback, and returns to York.
- Autumn –The Great Heathen Army, led by Ivar the Boneless and Ubba, invades East Anglia, and plunders Peterborough. The Vikings take up winter quarters at Thetford.
- November 20 – King Edmund the Martyr and his East Anglian army are destroyed by the Vikings. He is captured, tortured, beaten and used as archery practice.
- The Zanj Rebellion: The Zanj (black slaves from East Africa), provoked by mercilessly harsh labor conditions in salt flats, and on the sugar and cotton plantations of southwestern Persia, revolt.
- Summer – Caliph Al-Mu'tazz is murdered by mutinous Muslim troops, after a 3-year reign. He is succeeded by Al-Muhtadi (a grandson of former Al-Mu'tasim), as ruler of the Abbasid Caliphate.
- July 9 – The 869 Sanriku earthquake and associated tsunami devastate a large part of the Sanriku coast on the northeastern side of the island of Honshu.
- The last monument ever erected at Tikal, Stela 11, is dedicated by ruler (ajaw) Jasaw Chan Kʼawiil II.
- The Fourth Council of Constantinople is called by Basil I and Pope Adrian II. The council condemns Photius I, and deposes him as patriarch. His predecessor Ignatios is reinstated.
- February 14 – Cyril, Byzantine missionary and bishop
- August 8 – Lothair II, king of Lotharingia (b. 835)
- September 8 – Ahmad ibn Isra'il al-Anbari, Muslim vizier
- September 18 – Wenilo, Frankish archbishop
- October 14 – Pang Xun, Chinese rebel leader
- November 20 (or 870) – Edmund the Martyr, king of East Anglia
- Al-Darimi, Muslim scholar and imam
- Al-Hakim al-Tirmidhi, Muslim jurist (approximate date)
- Al-Jahiz, Afro-Muslim scholar and writer (or 868)
- Al-Mu'tazz, Muslim caliph (b. 847)
- Dongshan Liangjie, Chinese Buddhist teacher (b. 807)
- Dúnlaing mac Muiredaig, king of Leinster (Ireland)
- Ermentrude of Orléans, queen of the Franks (b. 823)
- Gundachar, count (or margrave) of Carinthia
- Leuthard II, Frankish count (or 858)
- Rothad of Soissons, Frankish bishop
- Shapur ibn Sahl, Persian physician
- Solomon, Frankish count (approximate date)
- Yu Xuanji, Chinese poet (or 868)
- Kreutz, Barbara M. (1991). Before the Normans: Southern Italy in the ninth and tenth centuries. Philadelphia: University of Pennsylvania Press. p. 43. ISBN 0812231015.
- Hill, Paul (2009). The Viking Wars of Alfred the Great. pp. 32–6. ISBN 978-1-59416-087-5.
- Martin, Simon; Grube, Nikolai (2000). Chronicle of the Maya Kings and Queens: Deciphering the Dynasties of the Ancient Maya. London; New York: Thames & Hudson. ISBN 0-500-05103-8. OCLC 47358325.
- Rahner, Karl (2004). Encyclopedia of Theology. p. 389. ISBN 0-86012-006-6.