Niiname-sai is the Japanese harvest thanksgiving ceremony in which the emperor offers newly harvested rice to the gods.
The ceremony is a major imperial ritual associated with the Japanese agricultural year. Traditionally, the emperor presents the first rice and other newly harvested foods to Shinto deities, then partakes of the offerings. The rite expresses gratitude for the harvest and prayers for continued abundance.
Niiname-sai is held annually on November 23. Before Japan’s modern national-holiday system, the date was associated with a harvest festival known as niinamesai; November 23 is now Labor Thanksgiving Day, whose modern civic meaning developed after World War II.
Niiname-sai is distinct from ordinary local harvest celebrations and from New Year customs. It is specifically an imperial Shinto observance, although its underlying theme—giving thanks for the year’s crops—is shared by agricultural festivals worldwide.