Alvise da Cadamosto (ca. 1428-1483) was an Italian trader and traveler from Venice who discovered the Cape Verde Islands and described the Canary Islands and the Senegal-Gambia-Geba area.
Alvise da Cadamosto sailed aboard Venetian galleys to North Africa, Crete, Alexandria, and Flanders between 1445 and 1452. On returning to Venice in 1454 he found his father banished and his family in distress. Because of Cadamosto's knowledge of the spice trade, Prince Henry the Navigator offered him a Portuguese caravel for a trading venture down the western African coast, with the right to keep half the products with which he returned.
Cadamosto, in a caravel of some 70 modern tons, left for Lagos in March 1455. He called at the Madeira and Canary islands, then traveled along the African coast. In his reports he observed that the Senegal River divided the arid Saharan region from the fertile, forested areas to the south. Beyond the Senegal Cadamosto encountered two caravels, one under the command of the Genoan Usodimare, and the three vessels proceeded past Cape Verde to the mouth of the Gambia River. In the estuary of the Gambia, Cadamosto sketched the Southern Cross, and he referred to the height of the Pole Star as a fraction of a lance-length above the skyline; this notation suggests that navigators were not yet measuring latitude in degrees.
In 1456 Cadamosto and Usodimare, with license from Prince Henry, equipped two caravels which, with a third provided by Henry, set out for the Gambia. Beyond Cape Blanc the vessels encountered a gale, and Cadamosto, steering as close to the wind as possible, headed out to sea. Off Cape Verde an island came into view which he named Boa Vista. A shore party observed an island to the north (Sal) and two to the south (Maio and Sāo Tiago), and Cadamosto visited the last-named. Other islands of the archipelago were observed to the west.
Cadamosto sailed 60 miles up the Gambia and traded with a friendly chief until fever forced the vessels from the river. He named and charted several capes and rivers as far as the Rio Grande (Geba), which may have already been reached by Diogo Gomes; but he was the first to describe the Bissagos Archipelago.
Cadamosto's narrative, which was first published in 1507, gave valuable information about the caravan routes of the interior, from Mali via Ouadane to Morocco, from Mali via Timbuktu to Gao eastward, and from Timbuktu via Taghaza to Morocco and Tunis, and also described the trade, especially in gold and salt. G. R. Crone (1937) commented that Cadamosto's "is the first original account to have survived of a voyage into the regions opened up by European enterprise at the dawn of modern overseas expansion, and reflects the spirit of openminded enquiry characteristic of the new age."
The Voyages of Cadamosto was edited by G. R. Crone in 1937. Background studies include John W. Blake, European Beginnings in West Africa, 1454-1578 (1937); Boies Penrose, Travel and Discovery in the Renaissance, 1420-1620 (1952); Charles E. Nowell, The Great Discoveries and the First Colonial Empires (1954); and J. H. Parry, The Age of Reconnaissance (1963).