[3] He entered the Society of Jesus, where he was ordained priest, he received his doctorate in theology at the University of Coimbra, where he subsequently taught at the College of Arts.

The party crossed the desert into the Ethiopian highlands, and reached Fremona, the base of Catholic missionary efforts, on 21 June 1625, over two years after Mendes had left Lisbon.

[11] However, strife and rebellions over the enforced changes began within days of the public ceremony, and soon the Emperor's son, Fasilides sided with the indigenous Ethiopian Orthodox Church.

They reached Diu a month later, and Mendes immediately continued on to Goa, where he unsuccessfully sought military support for his restoration.

[14] He appears to have spent the rest of his life in Goa, where he wrote his book on Ethiopian history and geography and the Jesuit mission in Ethiopia, Expeditionis Aethiopicae.

[15] His letters and annual reports in Latin appear in other volumes of the series Rerum Aethiopicarum Scriptores Occidentales[16] and many have been translated into English.

Decades later, Merid Wolde Aregay suggested that Mendes feared appearing lax and weak in the eyes of his superiors in Rome and behaved accordingly.

... [His own letters and reports] suggest that Mendes was not, in fact, a hard-liner by personality but rather was implementing the new rules handed down by the new missionary oversight institution of the Sacra Congregatio de Propaganda Fide.