It is a shugo daimyo (shugo, which were Japanese provincial military governors, that became daimyo, which were Japanese feudal lords) with its base in Suo Province, and a gamily which grew up to be a daimyo (Japanese territorial lord) in the Sengoku period, and the Suo-Ouchi clan is famous.
周防国を本拠とする守護大名、戦国大名に成長した一族、周防大内氏が著名である。