The Sōma clan (相馬氏, Sōma-shi) was a Japanese samurai clan who ruled the northern Hamadōri region of southern Mutsu Province in the Tōhoku region of northern Japan for over 700 years, from the Kamakura period through the Meiji Restoration of 1868. The Sōma claimed descent from the Taira clan via the Chiba clan and took their name from the Chiba clan territories in Sōma District of northern Shimōsa Province. The clan moved its seat from Shimōsa to Mutsu Province in the early Kamakura period, and were confirmed as daimyō of Sōma Nakamura Domain under the Edo-period Tokugawa shogunate.