Vasco da Gama set out in 1497, and made his famous voyage round the Cape (calling at and naming Natal on the way) to Sofala, where he picked up an Arab pilot who took him to Malindi, and thence to India. On his return journey Vasco da Gama took cognizance of the island of Mozambique, and visited the Quelimane river near the mouth of the Zambezi. Numerous well-equipped expeditions sailed for India within the years following Vasco da Gama’s discoveries. While India was the main goal before the eyes of their commanders, considerable attention was bestowed upon the founding of forts along the East coast of Africa, both to protect the Cape route to India, and to further Portuguese trade with the interior of Africa. In nearly every case the Portuguese merely supplanted the Muhammadan Arabs, who—possibly succeeding Phoenicians or Sabaeans—had established themselves at Sofala, Quelimane, Sena (on the Zambezi), Moçambique, Kilwa, Zanzibar, Mombasa, Malindi, Lamu, and Magdishu. Sofala was taken by Pedro de Anhaya in 1505. Tristan d’Acunha hoisted the Portuguese flag on Sokotra Island and at Lamu in 1507, in which year also Duarte de Mello captured and fortified Moçambique. Kilwa and the surrounding Arab establishments were seized between 1506 and 1508; and a little later the remaining places already mentioned on the East coast of Africa were in possession of the Portuguese, who had also Aden on the south coast of Arabia, the island of Ormuz on the Persian Gulf, and various places on the coast of ’Oman, including Maskat. Meantime, for thirty years, Pero de Covilham remained a prisoner at the Court of the Emperor of Abyssinia, though treated with the utmost distinction. Before this period of the world’s history, and from the time of the earlier crusades, a legend had grown up of the existence of Prester (priest) Johannes—some Christian monarch of the name of John, who ruled in the heart of Asia or of Africa, a bright spot in the midst of Heathenry and Islam. The court of Prester John was located anywhere between Senegambia and China; but the legend had its origin probably in the continued existence of Greek Christianity in Dongola and Abyssinia. Pero de Covilham having at last located Abyssinia, and an Abyssinian envoy having proceeded to Lisbon in 1507 to invite an alliance, a Portuguese embassy sailed round the Cape of Good Hope to the Red Sea and landed (apparently at Masawa) in 1520. With this embassy were two priests, one of whom (Alvarez) thirty years afterwards wrote an interesting account of Northern Abyssinia. The priest-missionaries remained for a long time in Ethiopia; but the lay-members of the mission returned after a residence of five years, bringing Covilham away with them. But he died on the way back.