The Tachikawa-ryū (立川流) was a branch of Shingon Buddhism founded in the early 12th century by Ninkan (仁寛, died 1114), a monk of the Daigo-ji lineage of Shingon who was exiled in 1113 to the province of Izu (part of modern Shizuoka Prefecture) after being implicated in a plot to assassinate the then reigning emperor of Japan, Emperor Toba.