660

Year 660 was a leap year starting on Wednesday of the Julian calendar. The denomination 660 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.

Events

Emperor Constans II is paranoid about the ambitions of his younger brother, Theodosius, and has him murdered. Having attracted the hatred of the citizens of Constantinople, Constans decides to leave the Byzantine capital and moves to Syracuse.

The March of the Slavs, centred north of modern Klagenfurt, preserves independence and is first mentioned in historical sources, known as Carantania.
Felix, patrician of Toulouse, assumes the titles of Duke of Vasconia and Aquitaine. He is formally a vassal of the Franks, but rules "de facto" independently.

King Cenwalh of Wessex becomes dissatisfied with his local bishop, Agilbert of Dorchester, as he does not speak West-Saxon. Cenwalh splits the episcopal see of Wessex in two. Wine becomes the first bishop of Winchester, by the Saxons called Wintancestir. Agilbert resigns in protest and travels north to Northumbria.
King Sigeberht II of Essex is murdered by his brothers, Swithelm and Swithfrith, and other kinsmen for being "too ready to pardon his enemies"; that is to say, the Christians. Swithelm becomes king of Essex, with Swithfrith as joint-monarch for a period.
King Conall Crandomna of Dál Riata dies, and is succeeded by his nephew Domangart mac Domnaill.

July 9 - Battle of Hwangsanbeol: Sillan forces led by general Kim Yu-shin defeat the army of Baekje at Nonsan. During the fighting general Gyebaek dies at the hand of the Sillan invaders.
Baekje in southwestern Korea is conquered by an alliance of the Tang dynasty and Silla, led by general Su Dingfang and King Munmu of Silla. The Japanese envoys detained in Chang'an are paroled.
Emperor Gao Zong suffers from an illness. His wife Wu Zetian starts to rule the Chinese Empire.

Prince Naka no Ōe no Ōji of Japan makes a Japanese clock for the first time at Asuka, by which he causes the people to know the hours.
After the fall of Sabi to the forces of Silla, the Yamato government sends envoys directly to the Chinese court for the first time
The Baekje–Tang War begins, involving Yamato forces in support of the kingdoms of Baekje and Goguryeo
Japanese forces, under command of Abe no Hirafu, massacre the Mishihase people in Hokkaido
The capital of Japan moves from Asuka, Yamato to Asakura, Fukuoka