Year 655 (DCLV) was a common year starting on Thursday (link will display the full calendar) of the Julian calendar. The denomination 655 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.
|Ab urbe condita||1408|
|Balinese saka calendar||576–577|
|Chinese calendar||甲寅年 (Wood Tiger)|
3351 or 3291
— to —
乙卯年 (Wood Rabbit)
3352 or 3292
|- Vikram Samvat||711–712|
|- Shaka Samvat||576–577|
|- Kali Yuga||3755–3756|
|Minguo calendar||1257 before ROC|
|Seleucid era||966/967 AG|
|Thai solar calendar||1197–1198|
781 or 400 or −372
— to —
782 or 401 or −371
- Battle of the Masts: Emperor Constans II personally commands the Byzantine fleet (500 ships), and sets off to challenge the Arab navy. He sails to the province of Lycia (now in Turkey) in the southern region of Asia Minor. The two forces meet off the coast of Mount Phoenix, near the harbour of Phoenix (modern Finike). The Arabs under Abdullah ibn Sa'ad are victorious in battle, although losses are heavy for both sides. Constans barely escapes to Constantinople.
- November 15 – Battle of the Winwaed: King Oswiu of Bernicia defeats his rival, King Penda of Mercia at Cock Beck, near what later will be Leeds (Yorkshire). Kings Cadafael Cadomedd of Gwynedd and Œthelwald of Deira, allies of Mercia, withdraw their forces before the battle begins. It marks the defeat of the last credible pagan force in England. It also sows the seeds which will lead to Anglo-Saxon acceptance of the Catholic Church (approximate date).
- Oswiu becomes overlord (bretwalda) over much of Great Britain. He establishes himself as king of Mercia, setting up his son-in-law, Penda's son Peada, as a subject king over Middle Anglia.
- Empress Kōgyoku re-ascends to the throne of Japan, beginning a new reign as Saimei-tennō.
- Arab armies conquer Khurasan (Iran), and the Silk Road along Transoxiana (Central Asia).
- King Vikramaditya I of Chalukya (India) re-unites the kingdom, after defeating his brothers.
- May 15 – Pope Martin I is banished to Chersonesos Taurica (Ukraine). He dies later in the Crimean Peninsula after a 6-year reign, leaving Eugene I as the uncontested pope (see 654).
- Peada founds Peterborough Cathedral (Province of Canterbury). It becomes one of the first centres of Christianity in England. Deusdedit is consecrated to archbishop of Canterbury.
- September 16 – Pope Martin I
- November 15 – Æthelhere, king of East Anglia
- November 15 – Penda, king of Mercia
- Cadafael Cadomedd, king of Gwynedd
- Didier of Cahors, Frankish bishop
- Foillan, Irish missionary (approximate date)
- Loingsech mac Colmáin, king of Connacht (Ireland)
- Theodore Rshtuni, Armenian general
- Wang, empress of the Tang dynasty
- Xiao, concubine of Gao Zong
- Probably Mount Olympos south of Antalya, see "Olympus Phoinikous Mons" in Barrington Atlas of the Greek and Roman World, map 65, D4
- Warren Treadgold, A history of the Byzantine State and Society, Stanford University Press 1997, p. 314. ISBN 0-8047-2630-2
- Roberts, J: "History of the World". Penguin, 1994