March 3 on the Chinese lunar calendar is a traditional festival celebrated by many nationalities with varying methods across China. Formerly known as the "Shangsi Festival," it is observed by the Han people and a number of ethnic minority groups.
In ancient times, the first Si day (according to the year numbering system by the Heavenly Stems and Earthly Branches) was called "Shangsi" and celebrated as a festival. Most of the time, March 3 of the lunar calendar happened to be a Si day. So, after the Wei and Jin Dynasties, the Shangsi Festival was set on the third day of the third lunar month and renamed "the March 3 Festival". Originally March 3rd was more focused on religious activities to ward off disaster and keep evil spirits at bay as well as to pray for having children. The activities included sacrificial rituals in honor of Goddess Gao Mei, "Fu Xi" (a bathing ritual) and get-togethers attended by young men and women etc.
Lunar March 3 is the birthday of the Yellow Emperor (Huang Di), who was the first sovereign of civilized China, and is recognized as a common ancestor of all Han Chinese. The tradition of worshipping ancestors on the mythical leader’s birthday dates back to the Spring and Autumn Period (BC770-BC476). For thousands of years, Huangdi has been a symbol of Chinese civilization, and today he represents the desire for reunification of the nation. At present, big sacrifice ceremonies are held to commemorate the great ancestor in many parts of China, such as Hunan, Henan, Shaanxi Provinces.
There is a special custom on March 3 in Wuxi, Jiangsu Province--women who do not have children often eat pumpkin (Nan Gua). That’s because in Chinese, pumpkin has the same pronunciation as “male” (Nan). It is believed that women who eat pumpkin will have boys.