When Heraclius died in 641 AD, his sons Heraclonas and Heraclius Constantine took over as Byzantine emperors, ruling together. They only lasted a few years. Heraclius Constantine died within the year. His son Constantine (usually called Constans II) succeeded him, even though he was only 11 years old. Soon afterwards Heraclonas was also thrown out. The regents for little Constans ruled the Empire. This did not make for strong leadership. But also the Empire was very weak. The Umayyads held onto the territory they had gotten: Syria, Lebanon, Jordan, Israel, and Egypt. And they kept adding to it, working their way across North Africa to Carthage.
The Caliph Mu’awiya realized that the Islamic Empire needed warships if it was going to conquer Constantinople. So he began building a fleet. Mu’awiya attacked the island of Cyprus first, in 649, to see if the Roman fleet was any good, and he succeeded in taking it. Mu’awiya also made successful attacks on the islands of Rhodes and Crete. Constans counterattacked but was badly defeated. But at this dangerous moment, the Umayyad dynasty began a civil war between Mu’awiya and Ali. So they stopped attacking the Romans for a while (luckily for the Romans!).
Constans used the time to fight back the Slavs in Greece, Serbia, and Bosnia. He was more successful there. To make sure his sons became emperor after he died, Constans tonsured his brother, Tiberius, and then later had him murdered just to be sure. But killing his brother, combined with unsuccessful military campaigns against the Lombards in Italy, made him unpopular. Someone killed him in 668 AD, when he was 37 years old. But soon Constans’ son Constantine IV defeated the rebellion and became emperor.
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