Origins of Reiki Reiki was developed in the early 20th century by Mikao Usui (1865–1926), a Japanese spiritual seeker, teacher, and healer. According to tradition, Usui spent many years studying spiritual texts and healing methods from Buddhism, Shintoism, and other ancient teachings. Seeking a deeper understanding of healing and enlightenment, he undertook a 21-day meditation retreat on Mount Kurama, a sacred mountain near Kyoto. At the end of this retreat, Usui experienced a profound spiritual awakening. He reported receiving insight into how to access and channel healing energy—what became known as Reiki.