After Liu Bang's death, Emperor Gaozu usurped power, and others eradicated the forces of Lu and established himself as Emperor Gaozu. Because the night of cutting off Lu's clan happened to be the fifteenth day of the first month, Wendi went out of the palace incognito on the fifteenth night of the first month every year after he took office. The first month is also called January, so Emperor Wendi designated the fifteenth day of the first month as the Lantern Festival.

Extended data:

Lantern Festival customs

Lantern Festival is a traditional festival in China since ancient times. The appreciation of the Lantern Festival began in ancient times when people held torches in rural fields to drive away insects and wild animals, hoping to reduce pests and pray for a bumper harvest.

To this day, people in some areas in southwest China still use reeds or branches as torches on the 15th day of the first month, and hold high in groups to dance in fields or grain drying fields. Since the Sui, Tang and Song Dynasties, it has been in full swing. Tens of thousands of people took part in singing and dancing, from faint to dark. With the changes of society and times, the custom of Lantern Festival has changed greatly, but it is still a traditional folk festival in China.