856

856 in various calendars
Gregorian calendar	856; DCCCLVI
Ab urbe condita	1609
Armenian calendar	305; ԹՎ ՅԵ
Assyrian calendar	5606
Balinese saka calendar	777–778
Bengali calendar	263
Berber calendar	1806
Buddhist calendar	1400
Burmese calendar	218
Byzantine calendar	6364–6365
Chinese calendar	乙亥年 (Wood Pig); 3553 or 3346; — to —; 丙子年 (Fire Rat); 3554 or 3347
Coptic calendar	572–573
Discordian calendar	2022
Ethiopian calendar	848–849
Hebrew calendar	4616–4617
Hindu calendars
- Vikram Samvat	912–913
- Shaka Samvat	777–778
- Kali Yuga	3956–3957
Holocene calendar	10856
Iranian calendar	234–235
Islamic calendar	241–242
Japanese calendar	Saikō 3; (斉衡３年)
Javanese calendar	753–754
Julian calendar	856; DCCCLVI
Korean calendar	3189
Minguo calendar	1056 before ROC; 民前1056年
Nanakshahi calendar	−612
Seleucid era	1167/1168 AG
Thai solar calendar	1398–1399
Tibetan calendar	阴木猪年; (female Wood-Pig); 982 or 601 or −171; — to —; 阳火鼠年; (male Fire-Rat); 983 or 602 or −170

Millennium:	1st millennium
Centuries:	8th century; 9th century ; 10th century;
Decades:	830s; 840s; 850s ; 860s; 870s;
Years:	853; 854; 855; 856 ; 857; 858; 859;

Year 856 (DCCCLVI) was a leap year starting on Wednesday (link will display the full calendar) of the Julian calendar.

Events

March 15 – Emperor Michael III overthrows the regency of his mother Theodora. He appoints his uncle Bardas as the de facto regent and co-ruler of the Byzantine Empire.^[1]

King Charles the Bald cedes the county of Maine to Erispoe, ruler (duke) of Brittany—this in return for an alliance against the Vikings.
King Ordoño I of Asturias is said to have begun the repopulation of the town of León in the northwest of Spain (approximate date).

October 1 – King Æthelwulf of Wessex marries the 12- or 13-year-old Judith, daughter of Charles the Bald, at Verberie (Northern France). She is crowned queen and anointed by Hincmar, archbishop of Reims. The marriage is a diplomatic alliance between Wessex and the West Frankish Kingdom.^[2]
Winter – Æthelwulf returns to Wessex to face a revolt by his eldest son Æthelbald, who usurps the throne. Æthelwulf agrees to give up the western part of his kingdom, in order to avoid a civil war. He keeps control over Sussex, Surrey, Essex and Kent, over which Prince Æthelberht has presided.^[3]

November (approximate date) – An earthquake in Corinth, Greece kills an estimated 45,000 people.
December 3 – Another earthquake strikes the Abbasid Caliphate (modern-day Tunisia), also killing an estimated 45,000 people.
December 22 – Another earthquake strikes Damghan (modern-day Iran), killing an estimated 200,000 people.

^ Treadgold 1997, pp. 450–451.
^ Paul Hill (2009). The Viking Wars of Alfred the Great, p. 18. ISBN 978-1-59416-087-5.
^ Keynes 1998, p. 7; Abels 2002, p. 89.

Abels, Richard (2002). Morillo, Stephen (ed.). "Royal Succession and the Growth of Political Stability in Ninth-Century Wessex". The Haskins Society Journal: Studies in Medieval History. 12. Woodbridge, UK: Boydell & Brewer: 83–97. doi:10.1017/upo9781846150852.006 (inactive June 28, 2024). ISBN 1-84383-008-6.{{cite journal}}: CS1 maint: DOI inactive as of June 2024 (link)
Keynes, Simon (1998). "King Alfred and the Mercians". In Blackburn, Mark A. S.; Dumville, David N. (eds.). Kings, Currency and Alliances: History and Coinage of Southern England in the Ninth Century. Woodbridge, UK: The Boydell Press. pp. 1–45. ISBN 0-85115-598-7.
Treadgold, Warren (1997). A History of the Byzantine State and Society. Stanford, California: Stanford University Press. ISBN 0-8047-2630-2.