Which dynasty did the custom of celebrating the winter solstice come from?

The Winter Solstice Festival originated in the Han Dynasty, flourished in the Tang and Song Dynasties, and has been passed down to this day.

Before the Han Dynasty, because the first month of the weekly calendar was in 1 1 month, the winter solstice and New Year greetings were usually linked together, not carried out separately. After Emperor Wu of the Han Dynasty changed the summer calendar, the winter solstice and the first month were officially separated, and the winter solstice became a separate festival, which not only celebrated the whole country, but also had a five-day holiday. Now the winter solstice is also an important festival for us, and there are traditional customs, such as eating jiaozi.