Prester John (Latin: Presbyter Ioannes) was a mythical Christian patriarch, presbyter, and king. Stories popular in Europe in the 12th to the 17th centuries told of a Nestorian patriarch and king who was said to rule over a Christian nation lost amid the pagans and Muslims in the Orient.[1]: 28 The accounts were often embellished with various tropes of medieval popular fantasy, depicting Prester John as a descendant of the Three Magi, ruling a kingdom full of riches, marvels, and strange creatures.
At first, Prester John was imagined to reside in India. Tales of the Nestorian Christians' evangelistic success there and of Thomas the Apostle's subcontinental travels as documented in works like the Acts of Thomas probably provided the first seeds of the legend. After the coming of the Mongols to the Western world, accounts placed the king in Central Asia, and eventually Portuguese explorers came to believe that the term was a reference to Ethiopia, by which time it had been an isolated Christian "exclave" distant from any other Christian-ruled territory.