868

By place

Europe

• King Charles the Bald meets his brother Louis the German at Metz. They agree to a partition of Lotharingia, which belonged to former emperor Lothair I.
• Salomon, duke of Brittany, leads a joint campaign against the Loire Vikings. He is forced to defend southeastern Brittany unaided, and mobilizes levies raised at Poitiers to defeat the Vikings.
• Al-Andalus: The city of Mérida rises against the Umayyad rule. Emir Muhammad I regains control, and has the walls of the city destroyed. He supports the rival creation of Badajoz in retaliation.
• The County of Portugal is established around the town of Portus Cale by Vímara Peres, an Asturian nobleman, after the reconquest from the Moors of the region north of the Douro River.
• Ratramnus, a Frankish monk and abbot of Corbie Abbey, writes Contra Graecorum Opposita.

  Britain

• Alfred the Great marries Ealhswith. He supports his brother Æthelred I, in his choice to form an alliance with Mercia.
• King Burgred of Mercia appeals to Æthelred I for help in resisting the Great Heathen Army. The Danes occupy Nottingham, and stay through the winter without any serious opposition.
• King Áed Findliath drives the invading Danes and Norwegians out of Ireland, after defeating them at the Battle of Killineery.

  Africa

• September 15 - Ahmad ibn Tulun, a Turkish general, is sent to Egypt as governor, by the Abbasid caliph Al-Mu'tazz. He becomes the founder of the Tulunid Dynasty.
• Muslim Arab forces under Muhammad II, emir of the Aghlabid Dynasty, conquer the island of Malta and raid into the mainland of Italy.

  Asia

• May 11 - The earliest extant printed book, an illustrated scroll of the Diamond Sutra, unearthed at Dunhuang, is produced.