In 1488, Portuguese explorer Bartolomeu Dias (c. 1450-1500) became the first European mariner to round the southern tip of Africa, opening the way for a sea route from Europe to Asia. Dias’ ships rounded the perilous Cape of Good Hope and then sailed around Africa’s southernmost point, Cabo das Agulhas, to enter the waters of the Indian Ocean. Portugal and other European nations already had long-established trade ties to Asia, but the arduous overland route had been closed in the 1450s due to the Ottoman Empire’s conquest of the remnants of the Byzantine Empire. A major maritime victory for Portugal, Dias’ breakthrough opened the door to increased trade with India and other Asian powers. It also prompted Genoan explorer Christopher Columbus (1451-1506), then living in Portugal, to seek a new royal patron for a mission to establish his own sea route to the Far East.