For 10 points, name this Christian sect supposedly founded by St. Mark, based in Egypt.
The 1443 Cantate Domino proposed to reunite this sect with the Roman Church but was struck down by this group's pope, John XI. A convert to this sect named Annianus dated the Creation to March 25, 5492 BC, and believed in "Paschal Cycles" of 532 years that mark off periods known in this religion as the Era of Grace and the Era of Martyrs. This group was founded by those who disagreed with the Council of Chalcedon, the Monophysites. Its largest current monastery is at Wadi Natrun, and its current pope is Shenouda III. For 10 points, name this Christian sect supposedly founded by St. Mark, based in Egypt.
The 1443 Cantate Domino proposed to reunite this sect with the Roman Church but was struck down by this group's pope, John XI.
{Copts} [or {Coptic Christians}; or {Coptic Orthodox} Church; prompt on {Egyptian Christians} or similar {descriptive} answers]