64 A Short History of the Middle East
products of West Africa from Muslim hands; to make contact
south of the Sahara with the Negus of Ethiopia ('Prester John*)
and jointly assail the Muslims from the south; and he may also have
planned in his later life to win control for Portugal of the Indian
trade, which was now the main source of wealth of the Muslim
world.1 The progress of Portuguese exploration was naturally
slow at first, and by the time of Henry's death had gone no further
south than Sierra Leone; but in the following generation their
seamen pushed onwards, until in 1488 Bartholomew Diaz at last
rounded the Cape of Good Hope, Ten years later Vasco da Gama
went on to reach the Muslim coastal towns of East Africa, where he
secured an Indian pilot who conducted him on to Southern India.
The King of Portugal now adopted the grandiose title of'Lord of
the Conquest, Navigation, and Commerce of Ethiopia, Arabia,
Persia, and India', and in spite of Muslim resistance further trading
expeditions were sent to their station at Calicut, bringing home
cargoes of spices.
The Mamluks of Egypt and the Republic of Venice were equally
alarmed at this by-passing of their extremely profitable joint
monopoly of the Indian trade with Europe. The Mamluk Sultan
threatened to destroy the Christian Holy Places if the Portuguese
did not abandon their Indian voyages, and the Prior of St. Cather-
ine's Monastery on Sinai actually journeyed to Rome and tried to
persuade the Pope to forbid them. The Venetians, who had in-
stigated the so-called Fourth Crusade against Constantinople in
order to destroy a trade-rival and had looked with complacency on
the fall of the same city to the Ottoman Turks, even went so far as
to supply timber to the Mamluks to build warships in an attempt to
sweep the Portuguese from the Indian Ocean. But the Portuguese
ocean-going ships and mariners were more than a match for the
Muslim vessels and sailors, accustomed in the main to the more
sheltered seas of the Levant and the Middle East. They occupied
the strategically-placed islands of Socotra and Horrnuz in an
attempt to blockade the Muslim fleets within the Red Sea and the
Persian Gulf respectively, and repelled a Mamluk naval attack on
their Indian ports. Lisbon rapidly took the place of Venice as the
European clearing-house for Indian goods, and the Cape Route
began to supersede the old sea and land-routes to the Mediter-
ranean. Admiral de Albuquerque is even said to have formed a
1 Prestage, op. cit., 29 ff., 165 ff.