The Coptic Orthodox Church traces its roots back to St. Mark, the Evangelist who came to Egypt in the 1st century AD
The word "Copt" comes from aigyptos, the Greek for Egyptian.
Egyptians were quick to adopt the new faith in the hope of loosing themselves from Greek slavery. But thousands were persecuted and martyred in the process.
The persecution later continued under the Holy Roman Empire, this time over theological differences between the Coptic Church and Rome. For two centuries the Byzantine Empire waged an unsuccessful religious war against the Copts.
So when the Arab Muslim armies arrived from the Arabian Peninsula in 639, the persecuted Copts positively welcomed them.
Under the Muslim general Amr Ibn al-As, the Coptic patriarch or pope was protected against Rome's pressure, and the Christian community remained on good terms with its Arab conquerors for some years.
Later Arab caliphs, although they tended to favor those who adopted Islam, did not interfere much in the internal affairs of the church.
Copts were not converted to Islam in great numbers until the 10th century. And it was not until the 13th century that Muslims became the majority.
Over the centuries, the Coptic community has faced varying degrees of economic exploitation and open religious persecution. But by the 19th century, under the rule of Mohammad Ali (1805-1848), oppression largely ceased. From then on, especially under British rule, the number of Copts increased from a reported 150,000 in 1830 to about 6 million today - 10 percent of the population.