Muslim conquest of Egypt

At the commencement of the Muslim conquest of Egypt, Egypt was part of the Byzantine Empire with its capital in Constantinople. However, it had been occupied just a decade before by the Persian Empire under Khosrau II (616 to 629 AD).It was also religiously alienated. The orthodox Christianity of the Byzantines held to the doctrine of Christ having two natures, one divine and one human. In Egypt however the christological position of Miaphysitism prevailed, which supported the doctrine of Christ having only one "nature" in which Divinity and Humanity were united. Although the Christian Council of Chalcedon, held in 451, had ruled in favor of the orthodox position, Egypt had remained a hotbed of Miaphysite sentiment. So, with the restoration of Byzantine political control in 629, Emperor Heraclius began persecuting the Copts whom he considered Monophysites, expelling their patriarch (Oriental Orthodox are in fact miaphysites and not monophysites).
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