Source: Gordon J. Laing, Survivals of Roman Religion (New York: Longmans, 1931), pp. 82–84.

[p. 82] The pagan festivals of the dead seem to have been among those that showed persistence in survival. There are indications that they were celebrated even under Christian emperors…

But even after the pagan festivals ceased to be celebrated, the belief that the spirits of the dead could and, if properly approached, would give aid and protection to the living survived. The fathers of the Church saw that this was one of those inherent beliefs to which the people would cling with that unyielding pertinacity that manifests itself in the case of hereditary ideas. They compromised, shifting from the cult of the spirits of ancestors to the veneration of persons whose virtues, sufferings, or miraculous deeds justified their being regarded as intermediaries between God and man. [p. 83] In other words the Saints succeeded to the worship of the dead just as they succeeded to the cult of the departmental deities and to the "little gods" of the Roman household… While the Church never gave the Saints a higher place than that of intermediaries and intercessors whose aid might prove efficacious in gaining the favor of God, the masses of the population made no such fine distinctions, and confusing means and end came to regard the Saints themselves as present helps in trouble and addressed their prayers directly to them. They were more interested in their power to help them in their troubles than in their virtuous lives or harrowing deaths. Prior to the Reformation the efforts to check this tendency toward polytheism took the form of ecclesiastical legislation but this proved ineffectual.

Apart from the general doctrine of the veneration of Saints, there are some specific festivals of the modern Church that go back directly to pagan customs connected with the [p. 84] dead. One of these is All Saints’ Day, now celebrated on the first of November but till the time of Pope Gregory III observed on the thirteenth of May, which was one of the days of the Roman festival of the dead, the Lemuria. Whether there is any connection between these dates or not, the rites of All Saints’ Day are a survival not of the Lemuria but of the Parentalia. For in the modern festival the faithful visit the tombs of the Saints, venerate their relics, and pray for their blessing. The next day also, the second of November, All Souls’ Day, unquestionably reproduces some of the features of the Parentalia. People go in great numbers to the cemeteries and deck the graves of the members of their family with flowers and candles, and the mass, which takes the place of the ancient sacrifice, is directed to the repose of the souls of the departed.