|846 by topic|
|Ab urbe condita||1599|
|Balinese saka calendar||767–768|
|Chinese calendar||乙丑年 (Wood Ox)|
3542 or 3482
— to —
丙寅年 (Fire Tiger)
3543 or 3483
|- Vikram Samvat||902–903|
|- Shaka Samvat||767–768|
|- Kali Yuga||3946–3947|
|Japanese calendar||Jōwa 13|
|Minguo calendar||1066 before ROC|
|Seleucid era||1157/1158 AG|
|Thai solar calendar||1388–1389|
972 or 591 or −181
— to —
973 or 592 or −180
- Byzantine–Bulgarian War: The Bulgarians violate the peace treaty (see 815), and invade Macedonia along the River Struma. The cities of Serres and Philippi are devastated.
- Summer – Breton forces under Nominoe occupy the Frankish cities of Nantes and Rennes. He makes raids in Anjou and threatens Bayeux. King Charles the Bald recognizes him as duke of Brittany.
- Prince Pribina becomes a vassal of the Frankish Empire. King Louis the German grants him land near Lake Balaton (modern Hungary). He establishes Blatnohrad, capital of Balaton Principality.
- Frankish forces led by Louis the German invade Moravia. They encounter little resistance, and depose King Mojmir I from the throne. His relative, Rastislav, is set up as the new client ruler.
- Muslim forces attempt to raid Rome but only pillage the countryside around the city before being beaten back by Duke Guy I of Spoleto. In the aftermath, Pope Leo IV starts walling the area around the Vatican hill, creating the Leonine City
- The Mozarabs, Iberian Christians who live under Moorish rule, try to repopulate León in Al-Andalus (modern Spain). The city is recaptured by the Muslim Arabs.
- King Æthelred II of Northumbria sends military assistance to the Picts, in their fight against the invading Scots (approximate date).
- A Saracen Arab expeditionary force from Africa, consisting of 11,000 men and 500 horses, raid the outskirts of Rome, sacking the basilicas of Old St. Peter's and St. Paul's Outside the Walls.
- April 22 – Emperor Wu Zong (Li Chan) dies after a 6-year reign. He is succeeded by his uncle Xuān Zong, as Chinese ruler of the Tang Dynasty.
- Jang Bogo, a powerful maritime hegemon of Silla, is assassinated by aristocratic elements at his garrison headquarters by Yeom Jang (or 841).
- Gyeongmun, king of Silla (Korea) (d. 875)
- November 1 – Louis the Stammerer, king of West Francia (d. 879)
- Du Xunhe, Chinese poet (d. 904)
- Hasan al-Askari, 11th Shia Imam (d. 874)
- Li Yi, Chinese poet (approximate date)
- Rollo, Viking leader and count (approximate date)
- Wang Chao, Chinese warlord (d. 898)
- Zhang Chengye, Chinese eunuch official (d. 922)
- April 22 – Wu Zong, emperor of the Tang Dynasty (b. 814)
- July 29 – Li Shen, chancellor of the Tang Dynasty
- Bai Ju Yi, Chinese poet and official (b. 772)
- Dantivarman, king of the Pallava Empire (India)
- Ferdomnach, Irish monk and illuminator
- Jang Bogo, Korean maritime hegemon (or 841)
- Joannicius the Great, Byzantine theologian (b. 752)
- Li Zongmin, chancellor of the Tang Dynasty
- Mojmir I, king of Moravia (approximate date)
- Niall Caille, High King of Ireland
- Reginbert of Reichenau, German librarian
- Seguin II, Frankish nobleman
- Wang, concubine of Wu Zong
- Fine, John V. A. Jr. (1991) . The Early Medieval Balkans: A Critical Survey from the Sixth to the Late Twelfth Century. Ann Arbor: University of Michigan Press. p. 110. ISBN 0-472-08149-7.
- Goldberg 2006, p. 140.
- The Oxford companion to Irish history (2nd ed.). Oxford University Press. February 24, 2011. p. 26. ISBN 9780199691869.
- Goldberg, Eric J. (2006). Struggle for Empire: Kingship and Conflict under Louis the German, 817-876. Ithaca, NY: Cornell University Press. ISBN 9780801438905.