In 1507, the name “America” is given to a continent that in 250 years became home to the United States. The name was given in error. Martin Waldseemuller, a geographer, named the land in honor of Amerigo Vespucci. Waldseemuller, who had read letters by Vespucci, erroneously believed that Amerigo had discovered the continent.
Source: An Encyclopedia of American History in Chronological Order By Irving S. and Nell M. Kull.