Amerigo Vespucci (March 9, 1454 in Florence, Italy - February 22, 1512) was an Italian merchant and cartographer who voyaged to and wrote about the Americas. His exploratory journeys along the eastern coastline of South America convinced him that a new continent had been discovered, a bold contention in his day when everyone (except the Portuguese), including Christopher Columbus, thought the seafaring trailblazers setting out from European docks were travelling to East Asia and South Asia.

Amerigo Vespucci was born in Florence, Italy, as the third child of a respected family. His father was a notary for the Money Changers' Guild of Florence.

The role of Vespucci has been much debated, particularly due to two of his letters whose authenticity has been brought into doubt: the Mundus Novus (New World) and the Lettera (or "The Four Voyages"). While some have suggested that Vespucci was exaggerating his role and constructed deliberate fabrications, others have instead proposed that the two letters were forgeries written by others of the same period. Upon arriving off of the coast of South America, Amerigo wrote back to Italy announcing that the land masses they explored were much larger than anticipated and unlike the Asia described by earlier Europeans and, therefore, must be a New World, i.e., a previously unknown Fourth Continent, after Europe, Asia, and Africa.