Kūkai in the context of "Shingon Buddhism"

Chinese Esoteric Buddhism refers to traditions of Tantra and Esoteric Buddhism that have flourished among the Chinese people. The Tantric masters Śubhakarasiṃha, Vajrabodhi and Amoghavajra, established the Esoteric Buddhist Zhenyan (Chinese: 真言, "true word", "mantra") tradition from 716 to 720 during the reign of Emperor Xuanzong of Tang. It employed mandalas, mantras, mudras, abhiṣekas, and deity yoga. The Zhenyan tradition was transported to Japan as Tendai and Shingon Buddhism by Saichō and Kūkai, as well as influencing Korean Buddhism and Vietnamese Buddhism. The Song dynasty (960–1279) saw a second diffusion of Esoteric texts. Esoteric Buddhist practices continued to have an influence into the late imperial period and Tibetan Buddhism was also influential during the Yuan dynasty period and beyond. In the Ming dynasty (1368–1644) through to the modern period, esoteric practices and teachings became absorbed and merged with the other Chinese Buddhist traditions to a large extent.

In Chinese these traditions are also termed Mìjiào (Chinese: 密教; Esoteric Teaching), Mìzōng (密宗; "Esoteric Tradition") or Tángmì (唐密; "Tang (Dynasty) Esoterica").

The Shikoku Pilgrimage (四国遍路, Shikoku Henro) or Shikoku Junrei (四国巡礼) is a multi-site pilgrimage of 88 temples associated with the Buddhist monk Kūkai (Kōbō Daishi) on the island of Shikoku, Japan. A popular and distinctive feature of the island's cultural landscape, and with a long history, large numbers of pilgrims, known as henro (遍路), still undertake the journey for a variety of ascetic, pious, and tourism-related purposes. The pilgrimage is traditionally completed on foot, but modern pilgrims use cars, taxis, buses, bicycles, or motorcycles, and often augment their travels with public transportation. The standard walking course is approximately 1,200 kilometres (750 mi) long and can take anywhere from 30 to 60 days to complete.

In addition to the 88 "official" temples of the pilgrimage, there are 20 bekkaku (別格) temples, which are officially associated with the Shikoku Pilgrimage (and hundreds more bangai (番外) temples, simply meaning "outside the numbers", which are not considered part of the official 88). To complete the pilgrimage, it is not necessary to visit the temples in order; in some cases, pilgrims complete the journey in reverse, a practice known as gyaku-uchi (逆うち).