The 8th century is the period from 701 through 800 (DCCC) in accordance with the Julian Calendar.
The 640s decade ran from January 1, 640, to December 31, 649.
The 660s decade ran from January 1, 660, to December 31, 669.
The 670s decade ran from January 1, 670, to December 31, 679.
The 680s decade ran from January 1, 680, to December 31, 689.
Year 680 (DCLXXX) was a leap year starting on Sunday of the Julian calendar. The denomination 680 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.
Year 641 (DCXLI) was a common year starting on Monday of the Julian calendar. The denomination 641 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.
Constans II, nicknamed "the Bearded", was the Byzantine emperor from 641 to 668. Constans was the last attested emperor to serve as consul, in 642, although the office continued to exist until the reign of Leo VI the Wise. His religious policy saw him steering a middle line in disputes between the Orthodoxy and Monothelitism by refusing to persecute either and prohibited discussion of the natures of Jesus Christ under the Type of Constans in 648. His reign coincided with Muslim invasions under, Umar, Uthman, and Mu'awiya I in the late 640s to 660s. Constans was the first emperor to visit Rome since the fall of the Western Roman Empire in 476, and the last one to visit Rome while it was still held by the Empire.
Constantine IV, called the Younger and sometimes incorrectly the Bearded out of confusion with his father, was Byzantine emperor from 668 to 685. His reign saw the first serious check to nearly 50 years of uninterrupted Islamic expansion, most notably when he successfully defended Constantinople from the Arabs. His calling of the Sixth Ecumenical Council saw the end of the monothelitism controversy in the Byzantine Empire; for this, he is venerated as a saint in the Eastern Orthodox Church, with his feast day on September 3.
Mizizios or Mezezius was an Armenian noble who served as a general of Byzantium, later usurping the Byzantine throne in Sicily from 668 to 669.
The first Arab siege of Constantinople in 674–678 was a major conflict of the Arab–Byzantine wars, and the first culmination of the Umayyad Caliphate's expansionist strategy towards the Byzantine Empire, led by Caliph Mu'awiya I. Mu'awiya, who had emerged in 661 as the ruler of the Muslim Arab empire following a civil war, renewed aggressive warfare against Byzantium after a lapse of some years and hoped to deliver a lethal blow by capturing the Byzantine capital of Constantinople.
The Byzantine Empire was ruled by emperors of the dynasty of Heraclius between 610 and 711. The Heraclians presided over a period of cataclysmic events that were a watershed in the history of the Empire and the world. Heraclius, the founder of his dynasty, was of Armenian and Cappadocian (Greek) origin. At the beginning of the dynasty, the Empire's culture was still essentially Ancient Roman, dominating the Mediterranean and harbouring a prosperous Late Antique urban civilization. This world was shattered by successive invasions, which resulted in extensive territorial losses, financial collapse and plagues that depopulated the cities, while religious controversies and rebellions further weakened the Empire.
Fausta was the Byzantine empress as the wife of Constans II, when they married in 642.
The Typos of Constans was an edict issued by eastern Roman emperor Constans II in 648 in an attempt to defuse the confusion and arguments over the Christological doctrine of Monotheletism. For over two centuries, there had been a bitter debate regarding the nature of Christ: the orthodox Chalcedonian position defined Christ as having two natures in one person, whereas Miaphysite opponents contended that Jesus Christ possessed but a single nature. At the time, the Byzantine Empire had been at near constant war for fifty years and had lost large territories. It was under great pressure to establish domestic unity. This was hampered by the large number of Byzantines who rejected the Council of Chalcedon in favour of Monophysitism.
Saborios or Saborius was a Byzantine general who rose in revolt against Emperor Constans II in 667–668. He sought and obtained the aid of the Caliph Muawiyah I, but was killed in a horse accident before confronting the imperial troops.
Heraclius was Byzantine co-emperor from 659 to 681. He was the son of Emperor Constans II and Fausta, who was elevated in 659, before his father departed for Italy. After the death of Constans, Heraclius' brother Constantine IV ascended the throne as senior emperor. Constantine attempted to have both Heraclius and Tiberius removed as co-emperors. However, this sparked a popular revolt in 681. Constantine ended the revolt by promising to accede to the demands of the rebels, sending them home, but bringing their leaders into Constantinople. Once there, Constantine had them executed, then imprisoned Tiberius and Heraclius and had their noses slit, after which point they disappear from history.
Tiberius was Byzantine co-emperor from 659 to 681. He was the son of Constans II and Fausta, who was elevated in 659, before his father departed for Italy. After the death of Constans, Tiberius' brother Constantine IV, ascended the throne as senior emperor. Constantine attempted to have both Tiberius and Heraclius removed as co-emperors, which sparked a popular revolt, in 681. Constantine ended the revolt by promising to accede to the demands of the rebels, sending them home, but bringing their leaders into Constantinople. Once there, Constantine had them executed, then imprisoned Tiberius and Heraclius and had them mutilated, after which point they disappear from history.
Gennadius, was a Byzantine general who exercised the role of Exarch of Africa from 648 to 665. In 664 Gennadius rebelled against Emperor Constans II and was himself overthrown the next year by a loyalist uprising. He is sometimes enumerated as Gennadius II in reference to the 6th century governor of Africa with the same name.
Abu al-A'war Amr ibn Sufyan ibn Abd Shams al-Sulami, identified with the Abulathar or Aboubacharos of the Byzantine sources, was an Arab admiral and general, serving in the armies of the Rashidun caliphs Abu Bakr, Umar and Uthman rejecting the fourth Rashidun caliph Ali, instead serving Umayyad caliph Mu'awiya I.
