Historians still dispute the authorship and veracity of these accounts, but they were instrumental in raising awareness of the discoveries and enhancing the reputation of Vespucci as an explorer and navigator.

The claim inspired cartographer Martin Waldseemüller to recognize Vespucci's accomplishments in 1507 by applying the Latinized form "America" to a map showing the New World.

In 1505, he was made a subject of Castile by royal decree, and he was appointed to the position of piloto mayor (master navigator) for Spain's Casa de Contratación (House of Trade) in Seville in 1508, a post which he held until his death in 1512.

Vespucci was born on 9 March 1454 in Florence, a wealthy Italian city-state and a center of Renaissance art and learning,[5] in the suburb of Peretola.

[11] Amerigo's career path seemed less certain; instead of following his brothers to the university, he remained in Florence and was tutored by his uncle, Giorgio Antonio Vespucci, a Dominican friar in the monastery of San Marco.

Fortunately for Amerigo, his uncle was one of the most celebrated humanist scholars in Florence at the time and provided him with a broad education in literature, philosophy, rhetoric, and Latin.

[15] Meanwhile, he continued to show an interest in geography, at one point buying an expensive map made by the master cartographer Gabriel de Vallseca.

[14][page needed] In addition to managing Medici's trade in Seville, Berardi had his own business in African slavery and ship chandlery.

His motivations for leaving Florence are unclear; he continued to transact some business on behalf of his Medici patrons but more and more he became involved with Berardi's other activities, most notably his support of Christopher Columbus's voyages.

He continued to provision ships bound for the West Indies, but his opportunities were diminishing; Columbus's expeditions were not providing the hoped-for profits, and his patron, Lorenzo di Pierfrancesco Medici, was using other Florentine agents for his business in Seville.

A letter, addressed to Florentine official Piero Soderini, dated 1504 and published the following year,[25] purports to be an account by Vespucci of a voyage to the New World, departing from Spain on 10 May 1497, and returning on 15 October 1498.

[26] Others point to the inconsistencies in the narrative of the voyage, particularly the alleged course, starting near Honduras and proceeding northwest for 870 leagues (about 5,130 km or 3,190 mi)—a course that would have taken them across Mexico to the Pacific Ocean.

[27] Certain earlier historians, including contemporary Bartolomé de las Casas, suspected that Vespucci incorporated observations from a later voyage into a fictitious account of this supposed first one, so as to gain primacy over Columbus and position himself as the first European explorer to encounter the mainland.

[32] The vessels left Spain on 18 May 1499 and stopped first in the Canary Islands before reaching South America somewhere near present-day Suriname or French Guiana.

From there the fleet split up: Ojeda proceeded northwest toward modern Venezuela with two ships, while the other pair headed south with Vespucci aboard.

He assumed they were on the coast of Asia and hoped by heading south they would, according to the Greek geographer Ptolemy, round the unidentified "Cape of Cattigara" and reach the Indian Ocean.

[34] In 1501, Manuel I of Portugal commissioned an expedition to investigate a landmass far to the west in the Atlantic Ocean encountered unexpectedly by a wayward Pedro Álvares Cabral on his voyage around Africa to India.

Vespucci's reputation as an explorer and presumed navigator had already reached Portugal, and he was hired by the king to serve as pilot under the command of Gonçalo Coelho.

He was also charged with compiling a "model map", the Padrón Real, based on input from pilots who were obligated to share what they learned after each voyage.

[44] His nephew Giovanni was hired into the Casa de Contratación where he spent his subsequent years spying on behalf of the Florentine state.

[45] A few days ago I wrote you at some length about my return from those new regions we searched for and found with the fleet, at the expense and by the command of the most serene King of Portugal, and which can properly be called a "New World", since our forebears had absolutely no knowledge of it, nor do any of those who are hearing about it today...On 7 August 1501,[b] we dropped our anchor off the shores of that new land, thanking God with solemn prayers and the celebration of the Mass.

The Soderini letter (1505) came to the attention of a group of humanist scholars studying geography in Saint-Dié, a small French town in the Duchy of Lorraine.

In 1506, they obtained a French translation of the Soderini letter as well as a Portuguese maritime map that detailed the coast of lands recently discovered in the western Atlantic.

In a preface to the Letter, Ringmann wrote I see no reason why anyone could properly disapprove of a name derived from that of Amerigo, the discoverer, a man of sagacious genius.

[51]A thousand copies of the world map were printed with the title Universal Geography According to the Tradition of Ptolemy and the Contributions of Amerigo Vespucci and Others.

[53] In 1513 Waldseemüller published a new map with the New World labelled "Terra Incognita" instead of "America", and the accompanying text names Columbus as discoverer.

[28] Opinions began to shift somewhat after 1857 when Brazilian historian Francisco Adolfo de Varnhagen wrote that everything in the Soderini letter was true.

While Magnaghi has been one of the chief proponents of a two-voyage narrative, Roberto Levellier was an influential Argentinian historian who endorsed the authenticity of all Vespucci's letters and proposed the most extensive itinerary for his four voyages.

[citation needed] A two-voyage thesis was accepted and popularized by Frederick J. Pohl (1944), and rejected by Germán Arciniegas (1955), who posited that all four voyages were truthful.

But that this their opinion is false and utterly opposed to the truth...my last voyage has made manifest; for in those southern parts I have found a continent more densely peopled and abounding in animals than our Europe or Asia or Africa, and, in addition, a climate milder and more delightful than in any other region known to us, as you shall learn in the following account.