This version is from Hungary. The song is in Latin, so that pilgrims from anywhere might have understood it if they had learned enough of the language to appreciate the Mass.
Most of these old Latin songs are called by their first few words. "Orientis Partibus" means, "Out of the east came..." Well, what came? This version from Italy gives you a good idea:
We are a little early for the Feast of the Ass, but this will give you time to plan.
[The 14th of January] is a particularly bittersweet feastday with a vivid, raucous history of celebration worthy of the medieval epoch. It is that of the Flight in Egypt, also known as Festum Asinorum, the Feast of the Ass....
This event, amongst others, was celebrated in the Middle Ages as a play, inspired by the pseudo-Augustinian "Sermo contra judaeos, paganos, et Arianos de Symbolo," (a sermon which I burn to read, being an adjuration both to Jews and Gentiles--historial, philosophical, and prophetic). At the climax of the lively procession, the ass exchanged the wizard Balaam, who was marching to curse God's chosen people, for the virgin Mother of God, who was flying into Egypt to save her Son. All fittingly culminated in the Mass, at the end of which the officiating priest did not say 'Ite Missa est' nor did the congregation respond 'Deo gratias.' Instead there was a startling exchange of: 'Heehaw, heehaw, heehaw!'You can read more about the Feast -- which was chiefly a French festival, though we have seen the appeal of the Latin song far afield -- in this article.