The Coptic Orthodox Church of Alexandria (Coptic: Ϯⲉⲕ'ⲕⲗⲏⲥⲓⲁ 'ⲛⲣⲉⲙ'ⲛⲭⲏⲙⲓ 'ⲛⲟⲣⲑⲟⲇⲟⲝⲟⲥ ti.eklyseya en.remenkimi en.orthodoxos ente alexandrias, literally: the Egyptian Orthodox Church of Alexandria) is the official name for the largest Christian church in Egypt. The Church belongs to the Oriental Orthodox family of churches, which has been a distinct church body since the Council of Chalcedon in AD 451, when it took a different position over Christological theology from that of the Eastern Orthodox and Western churches, then still in union. The precise differences in theology that caused the split are still disputed, highly technical and mainly concerned with the Nature of Christ. The foundational roots of the Church are based in Egypt but it has a worldwide following.