Untoan was established in 1411 by the Zen priest Keishitsu. It grew under the patronage of the Nagao clan, the powerful warlords of Echigo, and became one of the region’s most respected Zen temples.
From around age 7, young Kagetora (later Kenshin) was sent to Untoan at his brother Harukage’s order. Under the abbot Tenshitsu Koiku, he studied Zen, Buddhism, and classical learning. The ethical foundation — the principle of fighting for justice rather than personal gain — that Kenshin demonstrated throughout his life is said to have been formed during these years.