Gagaku (ががく) means "Ya Zheng's music" in Chinese. It is a kind of traditional music that flourished in Japan during the Heian period. It is also music played in a large-scale ensemble style. The music is mostly instrumental, and it is still the court music of Japan and is the oldest music form existing in the world. Gagaku was first introduced to Japan from China and Korea during the Nara period, and was later imitated and fused to produce Japanese Gagaku.

According to historical records, as early as 453 AD, during the funeral of Emperor Yun Gong, the King of Silla sent more than 80 musicians to Japan to play mourning music; During his reign, Baekje of Korea sent another team of musicians to Japan; during the regency of Prince Shotoku, he sent envoys to the Tang Dynasty nineteen times to learn Chinese Tang music and bring it back to Japan; the envoy to the Tang Dynasty, Fujiwara Shintoshi, came to Japan in 835 Chang'an, learned pipa, and later returned to China with pipa and music scores...

In 701 AD, the Japanese Ministry of Administrative Affairs set up a special agency to take charge of foreign music, and Gagaku was originally the general name for foreign music. In the second year of Dabao (703), according to the "Dabao Ryulu", Japan set up the Gagaku Ryo to train professional musicians and musicians, and only serve the court, which made Gagaku move towards professionalization and elegance, and influenced Gradually grow.

So Japanese Gagaku evolved from ritual music in China, the Korean Peninsula, and South Asia. This music was introduced to Japan before the Middle Ages. Gagaku is ceremonial music in China, but the Tang music repertoire imported from China in Japanese Gagaku is considered to have evolved from the banquet music Yanraku of the Tang Dynasty. Since they have also absorbed the nutrients of traditional Chinese music, the relationship between Japanese gaku, Vietnamese gage and Korean traditional music can be said to be equivalent to that of brothers. Although the exotic names of Tang music, Korean music, and Lam Yi music (Vietnamese music) remain in the music classification, Japanese Gagaku also contains elements of ancient music before the introduction of mainland music. Coupled with the mutual influence between Gagaku, folk songs, and statements (Buddhist hymns with rhyme lyrics, divided into Sanskrit, Han, and Harmony), Gagaku formed a unique form in Japan. At present, the Shikibu Music Club of the Imperial Household Agency of the Cabinet Office of Japan has inherited about a hundred pieces of music.

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