668

By place

Byzantine Empire

• September 15 - Emperor Constans II is killed under mysterious circumstances in his bath, during a mutiny at Syracuse. The Byzantine court returns to Constantinople after an absence of 5 years, in which the Muslim-Arabs have made annual invasions and devastations of Anatolia. Probably assassinated by his chamberlain after a 27-year reign, Constans is succeeded by his son Constantine IV, alongside his brothers Heraclius and Tiberius as co-emperors.
• Mezezius, Byzantine general and patrikios, is proclaimed emperor by the army in Syracuse. Constantine IV organizes an expedition to suppress the military revolt in Sicily.

  Europe

• Ebroin, mayor of the palace, becomes de facto ruler of Neustria and "of the Franks". According to Bede, he runs the nation's foreign policy and internal security.
• Kotrag, ruler of Great Bulgaria, leads the Khazars in overthrowing his brother Batbayan of the Onogurs, and moves south into the Caucasus Mountains.
• Asparukh, leader of the Utigurs, leaves the Ongal area to Kotrag, and leads his people into Moesia in Northern Bulgaria.

  Arabian Empire

• Caliph Muawiyah I receives an invitation from Saborios, Byzantine commander of the troops in Armenia, to help overthrow Constantine IV in Constantinople. He sends a Muslim army under his son Yazid, against the Byzantine Empire.
• Yazid reaches Chalcedon in Bithynia, and takes the important Byzantine center Amorium.
• Arab forces conquer the Garamantes in the Sahara desert.

  Asia

• Chinese troops sent by the Tang Dynasty emperor Gao Zong complete their conquest of the Korean Peninsula, making Korea a vassal state. Leaders of the expedition have been selected by the emperor's powerful concubine Wu Zetian. The kingdom of Goguryeo is overthrown; the Unified Silla period starts.
• Emperor Tenji of Japan hunts on the Moor of Ōmi-Gamōno. The letters exchanged between prince Ōama and princess Nukata are recorded in Man'yōshū.
• The monk Gyōki, one of the founders of Japanese Buddhism, is born in the Ōtori District of Kawachi Province.

  By topic

Religion

• Theodore of Tarsus is made archbishop of Canterbury. He introduces a strict Roman parochial system that becomes the model for the secular state.
• Colman of Lindisfarne, accompanied by 30 disciples, sails for Ireland, settling down at Inishbofin and founds a monastery.