622

By place

Byzantine Empire

• Byzantine–Sasanian War: Emperor Heraclius sails from Constantinople with an expeditionary force, and starts a counter-offensive against the Persian Empire. He lands a few days later at the junction of Cilicia and Syria, near Alexandretta and ancient Issus.
• Battle of Issus: Heraclius defeats the Persian forces under Shahrbaraz in Cappadocia. He recaptures Anatolia, but returns to Constantinople to deal with the threat posed to his Balkan domains by the Avars, and puts the Byzantine army into winter quarters in Pontus.

  Asia

• The Western Turks conquer the Oxus valley and cooperate with Heraclius against Persia, taking Khorasan.

  By topic

Religion

• September 9 or June 17 - The Islamic prophet Muhammad, after being warned of a plot to assassinate him, secretly leaves his home in Mecca to make the Hegira to Yathrib, along with his companion Abu Bakr. They take refuge in the Cave of Thawr south of Mecca for three days, departing on September 13 or June 21.
• September 20 or June 28 - Muhammad does not enter Yathrib directly, but stops at its outlying environs of Quba. He establishes the Quba Mosque here, the first mosque of Islam. On July 2 he makes his first visit to Yathrib for Friday prayers.
• October 4 or July 13 - After a fourteen days' stay in Quba, Muhammad finally moves from Quba to Yathrib, and is greeted cordially by its people. Here he drafts the Constitution of Medina, an agreement between the various Muslim, Jewish, Christian and pagan tribal communities in the city, forming the basis of a multi-religious Islamic state, and begins construction of the Al-Masjid an-Nabawi Mosque. Later during the caliphate of Umar in 638, the lunar year during which the emigration to Medina occurred is designated "Year One" of the new Hijri era.
• Xuanzang is fully ordained as a Buddhist monk at the age of 20.

  Births

• Abdullah ibn Aamir, Arab general
• Al-Mukhtar, Islamic revolutionary
• Bavo, Frankish nobleman and saint
• Mezezius, Byzantine usurper
• Uqba ibn Nafi, Arab general
• Xue Yuanchao, official of the Tang dynasty

  Deaths

• April 8 - Shōtoku, prince and regent of Japan
• Andronicus, Coptic Orthodox Patriarch of Alexandria
• Colmán mac Cobthaig, king of Connacht
• John of Biclaro, Visigoth chronicler
• Li Zitong, rebel leader during the Sui dynasty
• Lin Shihong, rebel leader during the Sui dynasty
• Liu Wuzhou, rebel leader during the Sui dynasty
• Walid ibn al-Mughirah, chief of the Banu Makhzum clan of the Quraysh tribe.