ABSTRACT
The Fifth Crusade took place between 1217 and 1221 in two theatres: the Holy Land and Egypt. Belief in Prester John here had an important impact on world history, being partly responsible for the failure of the crusade as a whole. Whilst the Fifth Crusaders were in northern Egypt after having made a few conquests there, news reached them of the first conquests of Chingis Khan in Asia, which called to mind Prester John. Around the same time, the leaders of the Fifth Crusade discovered a book of prophecies in Egypt that said that a king from the west and a king from the east would meet in Jerusalem and destroy Islam forever. This they took to mean that Prester John was coming from the east to help them win the crusade (Holy Roman Emperor Frederick II was believed to be the king from the west; he too never arrived).
