About Mugaku Sogen

Mugaku Sogen (無学祖元), also known as Bukko Kokushi was a prominent Zen Buddhist monk of the 13th century in Japan, an emigre from Song dynasty China. He was adviser to Japan's most powerful ruler of the day, the regent of the shōgun (Shikken) Hōjō Tokimune. He founded the Zen temple Engaku-ji in Kamakura, one of Japan's five most important Zen temples.

The Dharma transmission – Founders & patriarchs of Buddhist currents

A lineage in Buddhism is a line of transmission of the Buddhist teaching that is "theoretically traced back to the Buddha himself." The acknowledgement of the transmission can be oral, or certified in documents. Several branches of Buddhism, including Chan (including Zen and Seon) and Tibetan Buddhism maintain records of their historical teachers. These records serve as a validation for the living exponents of the tradition. In Chan and Zen Buddhism, transmission is a custom .