In the other cardinal point of the policy of John "the Great," the maintenance of a close alliance with England, John II. carefully followed the example of the founder of the house of Aviz. Affonso V. had not neglected this important tradition, and had even promised his sister, Donna Catherine, to Edward IV., in 1461, a marriage only frustrated by the death of the princess in 1463; and the English monarch had solemnly ratified the Treaty of Windsor in 1471, and again after the battle of Barnet in 1472, and he had also included the name of the King of Portugal, as an ally of England, in his treaty with Louis XI. of France, in 1475. John II. drew the bonds of friendship still closer, and sent important embassies to the three kings of England, who ruled in quick succession in this country. In 1482 Edward IV. ratified the Treaty of Windsor in the presence of the ambassadors of John II., and recognized his new title of "Lord of Guinea," and in 1484 Richard III. did the same. In 1485 the King of Portugal proposed in a Cortes held at Alçobaça, that his only sister Joanna should be given in marriage to Richard III., but the princess, who was famed for her piety and wished to become a nun, fortunately for herself, refused the alliance, as she afterwards did the hand of Charles VIII. of France. Henry VII. bore no enmity towards John II. on account of his friendship with Richard III., but, on the contrary, showed every disposition to assist him in his struggle with his nobility, and in 1488 went so far as to arrest the Count of Pennamacor, one of the insurgent Portuguese noblemen who had escaped to England, and to imprison him in the Tower. It was in this year also that the last treaty of commerce between England and Portugal, before the famous Methuen treaty in 1703, was concluded at Lisbon by Richard Nanfran and Thomas Savage, who had been sent for that purpose, and to invest John II. as a Knight of the Garter.
[Illustration: CHART OF GOA. (_From the Sloane MS. 197, folio 248._)]
But it was not only on account of his suppression of the power of the feudal nobility, and of his wise peace policy, that John "the Perfect" was beloved by his people, it was also because he showed himself a worthy successor of Prince Henry "the Navigator," in promoting exploration, and devoted his best energies to discovering a direct route to India. The two famous voyages of Diogo Cam and Bartholomeu Diaz, which had resulted in the discovery of the Congo and of the Cape of Good Hope, have been mentioned, but it was rather in other directions that the originality of mind which distinguished John II. showed itself. He was the first European monarch who thought that if it might be possible to reach India by sea by sailing round the continent of Africa, it might also be possible to find a road to "Cathay" by sailing round the continent of Europe to the north-east. On this mission he despatched Martim Lopes, who sailed past the North Cape into regions hitherto unexplored, and discovered the great island to the north of Russia, which still bears the name he gave it of Nova Zembla. John II. also had ideas of striking out new routes to India by land, or at least of exploring the land routes in order to correct prevalent geographical mistakes. With these ideas he sent forth the two first European explorers of the interior of Africa, Pedro de Evora and Gonçalo Annes, who managed to get as far as Timbuctoo. Still more important were the missions which he sent overland to India, and in search of that mythical Christian potentate, Prester John. The two travellers he despatched were João Peres de Covilhão and Affonso de Payva. The former of these enterprising men made his way safely to India by following the regular trade route and accompanying the caravans. He visited both Goa and Calicut, and though he was refused a passage to the Cape, he managed to find his way back to Arabia, and eventually to Abyssinia, where he became the chief adviser and almost prime minister of the king, at whose capital he died. The other traveller, Affonso de Payva, went direct to Abyssinia, where the mythical Prester John was supposed to reign, and also died there.