|Centuries:||7th century – 8th century – 9th century|
|Decades:||730s 740s 750s – 760s – 770s 780s 790s|
|Years:||763 764 765 – 766 – 767 768 769|
|766 by topic|
|State leaders – Sovereign states|
|Birth and death categories|
|Births – Deaths|
|Establishment and disestablishment categories|
|Establishments – Disestablishments|
|Ab urbe condita||1519|
|Chinese calendar||乙巳年 (Wood Snake)
3462 or 3402
— to —
丙午年 (Fire Horse)
3463 or 3403
|- Vikram Samvat||822–823|
|- Shaka Samvat||688–689|
|- Kali Yuga||3867–3868|
|Japanese calendar||Tenpyō-jingo 2
|Minguo calendar||1146 before ROC
|Seleucid era||1077/1078 AG|
|Thai solar calendar||1308–1309|
Year 766 (DCCLXVI) was a common year starting on Wednesday (link will display the full calendar) of the Julian calendar. The denomination 766 for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years.
- August 25 – Emperor Constantine V publicly humiliates 19 high-ranking officials in the Hippodrome of Constantinople, after discovering a plot against him. He executes the leaders, Constantine Podopagouros and his brother Strategios, and blinding and exiling the rest.
- Autumn – Siege of Kamacha: Abbasid forces under Al-Hasan ibn Qahtaba are defeated at the fortress city of Kamacha in eastern Cappadocia (modern Turkey). A Byzantine relief army (12,000 men) forces the Muslim Arabs to retreat into Armenia.
- Sabin, ruler (khagan) of Bulgaria, flees to the Byzantine fortress city of Mesembria, from where he escapes to Constantinople. Constantine V arranges for the transfer of Sabin's family from Bulgaria who goes in exile.
- Baghdad nears completion as 100,000 laborers create a circle city about 2 km in diameter, leading it to be known as the "Round City". In the center is a palace build for caliph Al-Mansur, the capital is ringed by three lines of walls (approximate date).
- The Karluks, defeat the Turgesh Khaganate in Central Asia. Most of Turkestan (former Onoq territory) under Karluk rule except west of Lake Aral where a loose confederation named Oghuz Turks is about to emerge.
- Summer – Patriarch Constantine II is deposed and jailed after the discovery of Constantine Podopagouros' plot against Constantine V. Nicetas I is appointed patriarch of Constantinople.
- Metten Abbey near the town of Deggendorf (Bavaria) is founded by Gamelbert of Michaelsbuch.
- Abdullah al-Aftah, Shī‘ah Imam and Muslim scholar
- March 6 – Chrodegang of Metz, Frankish bishop
- August 25 – Constantine Podopagouros, Byzantine official
- Fallomon mac Con Congalt, king of Mide (Ireland)
- Muhammad ibn al-Ash'ath al-Khuza'i, Muslim governor
- August 25 – Strategios Podopagouros, Byzantine general