Philip Hitti mentions in "History of the Arabs" that during medieval times in Europe, there was a widely-circulated religious romance fable called "Jehoshaphat and Barlaam". Based largely on this fable, both the Roman Catholic and Greek Orthodox churches canonized Jehoshaphat, a "Hindu Prince". Apparently the fable actually described events in Siddhartha Gautama's life, who is known to occidentals as the Buddha. Jehoshaphat, it seems, is none other than the Buddha himself, which actually means that Buddha has been canonized twice as a saint in the christian religion.
see also: Barlaam and Josaphat in the Catholic Encyclopedia.