Raphael Hythloday is a Portuguese explorer of the New World, in the Utopia of Sir Thomas More (1516).
More's book makes reference to Amerigo Vespucci's account of his travels to the western continent, Four Voyages (1507), which states that the Portuguese navigator left twenty-four of his crew behind in Brazil. According to More, one of these was Raphael Hythloday, who continued to explore the continent of South America and eventually discovered the peninsular of Utopia, home to a perfect civilisation. Hythloday spent five years observing the natives before returning to Europe, where he encountered More in Antwerp.
Hythloday is mentioned by Philip José Farmer in Doc Savage: His Apocalyptic Life, where he is identified as an ancestor of Sarah Frobisher and through her, distantly, celebrated figures such as Doc Savage himself.