The Christian community in Egypt between 641 and 1517 was an often divided population in a state of constant transition. At the time of the Muslim conquest, the great majority of Egyptians were Christians of some sort, Christianity having been the religion of the Byzantine rulers of Egypt for over 300 years. The gradual transition from majority to minority under Muslim rule was a complex process that had a lasting impact on most aspects of the Christian communities in Egypt. The traditional understanding of Egyptian Christianity after the conquest as being theologically and culturally fixed and moribund is far from the reality of the dynamic religious, social and cultural activities of the Egyptian Christians. Similarly, the traditional notion of the Christian population of Egypt being cut off from the rest of the world is misleading, since there was considerable interaction with the outside world, especially with other Christian populations under Muslim control. Although subject to varying degrees of pressure and persecution from Muslims, the Egyptian Christians suffered equally from internal divisions and sectarian infighting. In spite of their internal dissension and dwindling numbers, however, the Egyptian Christians managed to keep a distinctive culture and identity alive and active in the first nine centuries of Muslim rule.

According to later traditions, St. Mark the Apostle brought Christianity to Egypt in the mid-first century. The earliest documentary and archaeological attestations of Christianity in Egypt are considered to be from the second century, but such evidence does not become secure in date or common in occurrence until the third century.