Sōma clan
During early Kamakura period, the Sōma clan served as retainers of Minamoto no Yoritomo and were awarded lands in southern Mutsu Province for their role in the conquest of Hiraizumi in 1189. Thus, along with the Nanbu clan and Shimazu clan, they had the distinction of being one of the few clans which held onto their territories for over 700 years, from the Kamakura period through the Meiji Restoration.