In the time of the crusades, Europeans were looking for any allies in their battles against the Muslims for the Holy Land. Medieval writings often feature a fabulously wealthy Christian king in the East. This was Prester John. He was believed to be a member of the Nestorian Church, which was an independent Eastern Christian church that did not fall under the purview of the patriarch in Constantinople. He was supposed to be an ally against the Muslims for the crusaders to take advantage of.
The story of Prester John was first recorded by Bishop Otto of Freisling Germany in his Chronicon published in 1145. It was based on a report from Bishop Hugh of Gerbal in Syria to the papal court at Viterbo, Italy. According to the story recorded in the Chronicon, Prester John was a powerful Christian king who was the descendant of the Magi who visited the Christ Child. He was also said to be a formidable fighter who defeated the Muslim kings of Persia in battle taking their capital of Ecbatana. The only reason he did not recapture Jerusalem was because he could not cross the Tigris River. There was no more on the story until a letter appeared in 1165. Copies of a letter from Prester John to the Byzantine emperor Manuel I Komnenos began circulating. In this letter, Prester John’s kingdom is described as having crystal clear rivers of emeralds, massive amounts of gold, majestic animals and the Ten Lost Tribes of Israel. This myth also morphed into having Prester John’s kingdom being next door to the Garden of Paradise. A good ally to have. This letter were so persuasive that Pope Alexander III sent a return letter addressed to Prester John in 1177. It was being taken east by Alexander’s personal physician Philip. It is addressed to “the illustrious and magnificent king of the Indies and a beloved son of Christ.” Nothing more is mentioned of Philip or what happened to him and the letter.
However, all of this was fictional. It is thought that the battle being referred to was fought between the Mongol khan Yelu Dashi and the Seljuk sultan Sanjar in 1141. The Mongol khans who fought in this battle were not Christians, but Buddhists. However, many of their followers were Nestorian Christians. It’s also possible that Europeans that were unfamiliar with Buddhists may have assumed they were another sect of Christianity. The letter published in 1165 was fiction, however, it was translated from its original Latin into a variety of languages and distributed throughout Europe. Then word returned from the Fifth Crusade that Prester John’s grandson, King David, was fighting the Saracens. The problem? It wasn’t King David conquering all these lands. It was the Mongol ruler Genghis Khan. They tried to bend this new development around the legend by saying one of his favorite wives was a Nestorian Christian and that he was tolerant of other religious faiths as long as they didn’t make trouble. However, this didn’t really fit the narrative and the legends moved away from Prester John being a central Asian king.
Some additional legends, linked Prester John to kingdoms in Africa even though the original story placed him in Asia. Marco Polo had discussed Ethiopia as a Christian land fueling the rumors. In the 15th century, Italian and Portuguese explorers began searching for Prester John in Africa. Portuguese explorers began connecting a kingdom in present-day Ethiopia with Prester John’s realm. They made contact with the kingdom of Zara Yaqob, and decided this kingdom was the source of the wealth of Solomon. Prester John was identified with the negus, or emperor, of the kingdom. In fact, ambassadors from Zara Yaqob attended the Council of Florence and identified as representatives of Prester John. They were extremely confused.
By this time, the legend was dying out as exploration of Africa and Asia by the Europeans were not finding this fabled kingdom. However, the legend did inspire generations of explorers, soldiers and dreamers