On 28 August 1439, Pope Eugene IV sent a message of unity with the Catholic Church to Ethiopian Emperor Constantine I,[5] but this effort was unsuccessful.

[6] With Islamic attacks up to 1531 threatening Christian Ethiopia, an appeal from the Emperor to the Portuguese brought support to defeat the Adal Sultanate in the Ethiopian–Adal War.

The next year, Pope Gregory XV named Afonso Mendes, a Portuguese Jesuit, Patriarch of the Ethiopian Church.

[6] In 1839, Italian Lazarist and Capuchins missionaries arrived, albeit within certain limitations imposed on them due to strong public opposition.

That same year, Justin de Jacobis was appointed first Prefect Apostolic of Abyssinia and entrusted with the foundation of Catholic missions in that country.

[1] The Latin Church had become established in the south of Ethiopia in areas that had not been Christian and that were incorporated into the modern country only at the end of the 19th century.

Ten years later, on 20 February 1961, an Ethiopic ecclesiastical province was established, with Addis Ababa as the Metropolitan See[2] and Asmara (in Eritrea) and Adigrat (in Ethiopia) as suffragan eparchies.