The Lantern Festival falls on the 15th day of the 1st lunar month, usually in February or March in the Gregorian calendar. As early as the Western Han Dynasty (206 BC-AD 25), it had become a festival with great significance.
This day's important activity is watching lanterns. Throughout the Han Dynasty (206 BC-AD 220), Buddhism flourished in China. One emperor heard that Buddhist monks would watch sarira, or remains from the cremation of Buddha's body, and light lanterns to worship Buddha on the 15th day of the 1st lunar month, so he ordered to light lanterns in the imperial palace and temples to show respect to Buddha on this day. Later, the Buddhist rite developed into a grand festival among common people and its influence expanded from the Central Plains to the whole of China.