646

By place

Byzantine Empire

• Arab-Byzantine War: Alexandria is recaptured by the Muslim Arabs, after a Byzantine attempt to retake Egypt fails, ending nearly 1,000 years of rule by Greco-Roman states in the city.
• Gregory the Patrician, Byzantine exarch of Africa, begins a rebellion against Constans II, and proclaims himself emperor; the revolt finds broad support among the populace.

Arabian Empire

• Caliph Uthman ibn Affan founds the city of Jeddah on the coast of the Red Sea. He establishes a port for Muslim pilgrims making the required Hajj to Mecca.

Africa

• Battle of Nikiou: The Rashidun army under Amr ibn al-'As defeats a smaller Byzantine force, near the fortified town of Nikiou.
• Amr ibn al-'As builds fortifications in Alexandria and quarters a strong garrison in the vicinity, which twice a year is relieved from Upper Egypt.

China

• Summer - Emperor Taizong of the Tang dynasty destroys the Xueyantuo state, during the campaign against the Xueyantuo.

Japan

• Emperor Kōtoku makes a decree about the policies of building tombs. He discontinues the old customs of sacrificing people in honor of a dead man, and forbids ill-considered rituals about purgation.
• A Great Reform edict changes Japan's political order. It will lead to the establishment of a centralized government with Kōtoku ruling from his palace, Naniwa Nagara-Toyosaki Palace, in Osaka.

By topic

Religion

• Xuanzang completes his book Great Tang Records on the Western Regions, which later becomes one of the primary sources for the study of medieval Central Asia and India.