Amerigo Vespucci was born and brought up by his uncle in the Republic of Florence, in what is now Italy. The Americas are generally believed to have derived their name from the feminized Latin version of his first name.

At the invitation of King Manuel I of Portugal, Vespucci participated as observer in several voyages that explored the east coast of South America between 1499 and 1502. Manuel's commander Pedro ?lvares Cabral, on his way to the Cape of Good Hope and India in 1500, had discovered Brazil at latitude 16簞52'S. Portugal claimed this land by the Treaty of Tordesillas, and the King wished to know whether it was merely an island or part of the continent that Spanish explorers had encountered further north.

Vespucci, having already been to the Brazilian shoulder, seemed the person best qualified to go as an observer with the new expedition Manuel was sending. Vespucci did not command at the start - the Portuguese captain was probably Gon癟alo Coelho - but ultimately took charge at the request of the Portuguese officers. Vespucci, in all probability, voyaged to America at the time noted, but he did not have command and as yet had no practical experience piloting a ship. On the first of these voyages he was aboard the ship that discovered that South America extended much further south than previously thought.