Year 866 (DCCCLXVI) was a common year starting on Tuesday of the Julian calendar.

Events

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By place

Byzantine Empire

• April 21 Bardas, the regent of the Byzantine Empire, is murdered by Basil the Macedonian at Miletus, while conducting a large-scale expedition against the Saracen stronghold of Crete.

  May 26 Basil the Macedonian is crowned co-emperor of the Byzantine Empire, and is adopted by the much younger Michael III.

Europe

• May 27 King Ordoño I, ruler of the Kingdom of Asturias, dies after a 16-year reign. He is succeeded by his son, Alfonso III, who later is referred to as "Alfonso the Great".

• July 2 Battle of Brissarthe: Frankish forces, led by Robert the Strong, are defeated by a joint Breton-Viking army.

• Louis II, Holy Roman Emperor, defeats the Saracen invaders who are ravaging southern Italy.

Britain

• The Great Heathen Army of the Vikings rides north to Northumbria. The Northumbrians are preoccupied with a civil war, and the Danes enter York unopposed.

Italy

• An army in Lucera is assembled by orders of Louis II in preparation for an attack on the Emirate of Bari.

Abbasid Caliphate

• October 17 Caliph al-Musta'in is put to death, after a 4-year reign. He is succeeded by al-Mu'tazz, who becomes the youngest Abbasid caliph to assume power.

• The Kharijite revolt against the Abbasid Caliphate begins in Al-Jazira (Upper Mesopotamia), which will last for 30 years.

Japan

• Fujiwara no Yoshifusa becomes regent (sesshō) to assist the child emperor Seiwa, starting the Fujiwara regency.

By topic

Religion

• Boris I, ruler (knyaz) of the Bulgarian Empire, sends a diplomatic mission, led by the Bulgarian nobleman Peter, to Rome, in an effort to renew ties with the West.

• Pope Nicholas I orders that all Catholics should abstain from eating the "flesh, blood, or marrow" of warm-blooded animals on Wednesdays and Fridays.

• Pope Nicholas I forbids the use of torture in prosecutions for witchcraft (approximate date).</onlyinclude>

Births

• June 10 Uda, emperor of Japan (d. 931)

• September 19 Leo VI, Byzantine emperor (d. 912)

• Carloman II, king of the West Frankish Kingdom (approximate date)

• Robert I, king of the West Frankish Kingdom (d. 923)

• Yao Yi, chancellor of Later Tang (d. 940)

Deaths

• April 21 Bardas, Byzantine chief minister and regent

• May 27 Ordoño I, king of Asturias

• June 21 Rodulf, Frankish archbishop

• July 2 Robert the Strong, Frankish nobleman

• July 16 Irmgard, Frankish abbess

• October 17 Al-Musta'in, Abbasid caliph

• Adelaide of Tours, Frankish noblewoman

• Al-Mu'ayyad, Abbasid prince

• Charles the Child, king of Aquitaine

• Eberhard, duke of Friuli

• Emenon, Frankish nobleman

• Hungerus Frisus, bishop of Utrecht

• Linji Yixuan, Chinese monk and founder of the Linji school

• Liudolf, duke of Saxony

• Ranulf I, Frankish nobleman (b. 820)

• Robert, Frankish nobleman (b. 834)

• Rudolph, Frankish nobleman

• Wang Shaoyi, general of the Tang Dynasty

• Yahya ibn Yahya, Idrisid emir of Morocco

References