As to Christian Rome, Rupert of Deutz is of opinion that processions had been performed there since Constantine’s days, and Beleth names Liberius as their originator. Although it is not impossible these writers may have gained their information from ancient sources, still one cannot draw any certain conclusion from their remarks. We have, however, sure proof of the introduction of Rogations by Bishop Mamertus of Vienne. That part of the country had been visited for a considerable period by various calamities and earthquakes. On Easter night, 469, the royal palace in Vienne was struck by lightning, which caused such a panic among the entire congregation assembled in church, that they fled from the building. Mamertus put himself into connection with the civil authorities and along with them organised the Litanies, which had been used before this time, but in an informal and irregular manner. It was ordained they should take place on the three days before the Ascension, that they should be accompanied by a fast, and that the slaves should do no servile work. This institution was soon imitated throughout the whole of Gaul. Under Bishop Sidonius Apollinaris they were adopted at Clermont, next the first Council of Orleans (511), in its twenty-seventh canon, prescribes them for the Frankish part of the country, and Avitus could say they had already spread throughout the whole world, and been accepted with eagerness.[425] Nevertheless there is no clear evidence in antiquity, to show how matters were arranged in Rome. Only when we come to the time of Gregory the Great, do we get detailed accounts which have been preserved by Gregory of Tours. In autumn of the year 589, a terrible inundation devastated the city of Rome, overthrowing the ancient buildings, destroying all provisions, and leaving behind it a pestilence which carried away Pope Pelagius II. in February 590. To avert the divine wrath, Gregory, as administrator of the vacant see, ordered a procession of especial solemnity.[426] It was apparently the procession of the 25th April, but carried out on a larger scale than heretofore. It may, however, have been an extraordinary procession such as had never before taken place, for its date is unknown, and it is not certain if the often quoted statement of Gregory really refers to it. In his numerous letters there is no mention of this procession.