Prester John or also known as Presbyter Johannes was popular in Europe from the 12th through 17th centuries, and told of a Christian patriach and king said to rule over a Christian nation lost amidst the Muslims and pagans in the Orient. Written accounts of this kingdom varies collections of medieval fantasy.
Pester John was said to be a descendant of one of the Three Magi, said to be a generous ruler and a virtuous man presiding over a realm full of riches and strange creatures.
There has not been any concrete proof whether his kingdom did in fact exist. The prospect of finding Prester John has since vanished although the tales continue to inspire throughout the 20th century.