Portuguese navigator and explorer who was the first European to reach the Congo River. In his quest to discover a sea route around Africa to India, King João of Portugal commissioned Diogo Cão to explore the region. Cão left Portugal in 1482 and sailed along the West Coast of Africa until he reached the mouth of the Congo. There he erected a stone pillar dedicated to Portuguese sovereignty of the area. He sailed further, to Cape Santa Maria along what is now the coast of Angola, and erected a second pillar. Upon his return to Lisbon in 1484, King John II honored him with a title of nobility in honor of his discoveries. Cão made his second voyage in around 1485, reaching Cape Cross in what is present-day Namibia.