Tango no Sekku

Tango no Sekku (端午の節句^?) also known as Ayame no hi (Iris festival) is one the five annual ceremonies that were traditionally held at the Japanese imperial court called Gosekku . It is the Japanese version of Double Fifth and was celebrated on the 5th day of the 5th moon in the lunar calendar or Chinese calendar. After Japan switched to the Gregorian calendar, the date was moved to May 5. The festival is still celebrated in China, Taiwan, Hong Kong and Macau as the Duanwu Festival or Tuen Ng Festival (Cantonese), in Korea as the Dano Festival, and Vietnam as the Tết Đoan Ngọ on the traditional lunar calendar date.

Tan means "beginning" and go means "Horse", referring to the Chinese zodiac name for the fifth lunar month.Sekku means a seasonal festival. There are five sekku, including O-Shogatsu (January 1), Hina Matsuri (March 3), Tanabata (July 7) and Kiku Matsuri (September 9th) along with Tango. Tango no Sekku marks the beginning of summer or the rainy season.

Although it is not known precisely when this day started to be celebrated, it was probably during the reign of the Empress Suiko (593–628 A.D.). In Japan, Tango no Sekku was assigned to the fifth day of the fifth month after the Nara period.

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