Heraclian dynasty

Chronology
Heraclius		610–641
with Constantine III as co-emperor, 613–641
Constantine III		641
with Heraklonas as co-emperor
Heraklonas		641
Constans II		641–668
with Constantine IV (654–668), Heraclius and Tiberius (659–668) as co-emperors
Constantine IV		668–685
with Heraclius and Tiberius (668–681), and Justinian II (681–685) as co-emperors
Justinian II		685–695, 705–711
with Tiberius as co-emperor, 706–711
Succession
Preceded by Justinian dynasty and Phocas		Followed by Twenty Years' Anarchy

Constans II (Greek: Κώνστας Β', Kōnstas II Latin: Heraclius Constantinus Augustus or Flavius Constantinus Augustus); 7 November 630 – 15 September 668), also called Constantine the Bearded (Kōnstantinos Pogonatos), was emperor of the Byzantine Empire from 641 to 668. He was the last emperor to serve as consul, in 642. Constans is a diminutive nickname given to the Emperor, who had been baptized Herakleios and reigned officially as Constantine. The nickname established itself in Byzantine texts and has become standard in modern historiography.

Constans was the son of Constantine III and Gregoria. Due to the rumours that Heraklonas and Martina had poisoned Constantine III, he was named co-emperor in 641. Later that same year his uncle was deposed, and Constans II was left as sole emperor.

Constans owed his rise to the throne to a popular reaction against his uncle and to the protection of the soldiers led by the general Valentinus. Although the precocious emperor addressed the senate with a speech blaming Heraklonas and Martina for eliminating his father, he reigned under a regency of senators led by Patriarch Paul II of Constantinople. In 644 Valentinus attempted to seize power for himself but failed.

Under Constans, the Byzantines completely withdrew from Egypt in 642, and Caliph Uthman launched numerous attacks on the islands of the Mediterranean Sea and Aegean Sea. A Byzantine fleet under the admiral Manuel occupied Alexandria again in 645, but after a Muslim victory the following year this had to be abandoned. The situation was complicated by the violent opposition to Monothelitism by the clergy in the west and the related rebellion of the Exarch of Carthage, Gregory the Patrician. The latter fell in battle against the army of Caliph Uthman, and the region remained a vassal state under the Caliphate until civil war broke out and imperial rule was again restored.

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