The Ouchi clan was a prominent samurai family in Japan during the late medieval period, particularly known for their influence in the Yamato region. They played a significant role in the Muromachi period and were known for their wealth and power, often serving as vassals to the Ashikaga shogunate. The clan's most notable leader was Ouchi Yoshihiro, who expanded their territory and established a stronghold in Suō Province. The Ouchi clan was also known for their cultural contributions, including the promotion of Noh theater and the arts, which helped shape the cultural landscape of Japan during their time.