Ethiopian Christianity begins with a shipwreck. In the fourth century, according to the church's own account, a Syro-Phoenician youth named Frumentius survived a Red Sea wreck, was taken into the Aksumite royal household, and eventually converted King Ezana. Frumentius travelled to Alexandria seeking clergy for the new church and was instead consecrated its first bishop by Athanasius himself, establishing a bond between the Ethiopian and Egyptian churches that lasted more than sixteen centuries. Every Ethiopian Abuna, or metropolitan, was thereafter a Coptic monk sent from Alexandria until the twentieth century.
The late fifth century brought the Nine Saints, monks associated with the Byzantine world who settled in Tigray, founded monasteries, and translated the Bible and patristic works into Ge'ez. Their monastic foundations, especially Debre Damo, became the seedbed of Ethiopian scholarship and church architecture, including the rock hewn churches later built at Lalibela. When the wider church divided at the Council of Chalcedon in 451 over how to describe the union of divine and human natures in Christ, Ethiopia followed Alexandria in rejecting the Chalcedonian formula, holding instead to Cyril of Alexandria's teaching of one united nature, Tewahedo in Ge'ez. That word became the church's own name for itself.
Autocephaly, full self-governance under an Ethiopian rather than Egyptian head, was a nineteenth and twentieth century goal tied to Ethiopian sovereignty during the era of European colonization in Africa. It was achieved in 1959, when Abuna Basilios was enthroned as the first Ethiopian Patriarch with the agreement of the Coptic Orthodox Church of Alexandria, senior see of the Oriental Orthodox communion the two churches share.