Saturnalia was an ancient Roman festival in honour of the god Saturn, held on 17 December of the Julian calendar and later expanded to 23 December. The popularity of Saturnalia continued into the 3rd and 4th centuries, and as the Roman Empire came under Christian influence, many of its customs were recast into or at least influenced the seasonal celebrations surrounding Christmas and the New Year. Many observers schooled in the classical tradition have noted similarities between the Saturnalia and historical revelry during the Twelve Days of Christmas and the Feast of Fools William Warde Fowler notes: " has left its traces and found its parallels in great numbers of medieval and modern customs, occurring about the time of the winter solstice."