The ancient Roman festival associated with the period preceding the winter solstice was Saturnalia.
Saturnalia honored Saturn and officially began on December 17 in the Roman calendar. During the late Republic and Imperial periods, celebrations expanded, in some eras lasting through December 23—placing them immediately before or alongside the winter solstice.
The festival began with a public sacrifice and banquet at the Temple of Saturn in the Roman Forum. Feasting, gift-giving, gambling, candles, and holiday greetings became prominent features. Social conventions were also temporarily relaxed: enslaved people could speak more freely, and masters symbolically served meals.
Saturnalia is often linked loosely with Christmas, but it was not simply an ancient Roman Christmas. The festivals had different religious meanings, and the popular claim that Christmas directly replaced Saturnalia oversimplifies a complex history of Roman seasonal observances.