According to the historical documents owned by the Hei clan, who were based during the Kamakura period in what today is the city of Miyako City in Iwate Prefecture, a man called Tameyori HEI (also known as Tameie, Yorimoto, or Yukimitsu), said to be the bereaved child of MINAMOTO no Tametomo, was awarded the territories of Hei and Kesen, and took the name of Hei for his clan.
鎌倉時代岩手県宮古市に本拠を置いた閉伊氏の資料には、源為朝の遺児とされる閉伊為頼（為家・頼基・行光とも）が源頼朝より閉伊、気仙を給わり閉伊氏を称したとある。