Here's what we know:
* The book was written in the 14th century, likely around 1357.
* The author claimed to be Sir John Mandeville, a knight from England who traveled extensively throughout the East.
* However, modern scholarship has proven that Sir John Mandeville was likely a fictional character. The book's author was probably a learned man, likely a cleric, who drew from various sources, including other travel accounts and fantastical stories, to create their narrative.
* The book was incredibly popular in its time, and numerous manuscripts exist in different languages.
Despite the mystery surrounding its author, "The Travels of Sir John Mandeville" remains a fascinating and important work, reflecting the medieval world's fascination with faraway lands and cultures.