into his kingdom in 1145, would have permitted so grave a limitation of the royal prerogative to arise for the first time; and, on the other hand, it is extremely probable that it should arise during the years of his minority, when, as we have seen, experiments in independence were quite the fashion. It is therefore practically certain that the Privilege de St. Romain began soon after 1135, though not so late as 1145. The year 1210, already mentioned, is the first date on which an actual record exists of the liberated prisoner's name. His crime is not mentioned, though we know that it involved the penalty of death. But the date is important because of the inquiry insisted on by the governor of the Castle, when the Chapter of the Cathedral claimed his release by exercising their famous Privilege. When the dispute was referred to Philip Augustus, who was naturally anxious to conciliate the powerful clergy in his new domains, the chevalier Richard (who was the military protector of the abbey of St. Medard at Soissons), was given to the canons, and in gratitude for this escape from mortal peril,[22] he granted the Cathedral the perpetual rent upon his public mill. [Footnote 22: "Cum essem in periculo corporis mei in regio carcere apud Rothomagum detentus," he says.] From this case it is clear that so glaring a renunciation of the incommunicable sovereign rights of life and death could only have been successfully obtained by the regular intercession made to each duke for the release of one prisoner every year; and the origin of that intercession can be explained with perfect probability by the persistent mediaeval custom of the "Mysteries" or Miracle Plays, which came into fashion as soon as the confreries of various trades had been consolidated, just about the time the craft guilds appeared in England, in 1130, a date that fits in very well with the beginning of St. Romain's "privilege." These Mysteries or Miracle Plays were, as has been noticed, often performed in the Parvis of the Cathedral, and their first object was to represent the truths of Scripture to the people in the most intelligible and picturesque way. Ascension Day was one of the festivals of the Church which most especially needed some such educational and popular celebration, to impress upon men's minds how Christ by ascending to His Father to free them from the Devil and from everlasting death, had opened wide the gates of heaven, and _taken captivity captive_. No more striking significance could have been given to the meaning of the festival than by the public release of a prisoner who had been condemned to death. By slow degrees this release became an annual grace accorded to the Church in its holy office of public instructor.