Kiyomaro, a descendant of Nuteshiwake no Mikoto, who was Emperor Suinin's son, was bestowed the ason surname of "Wake," because of his distinguished service, and his descendants called themselves "the Utsumi clan."
垂仁天皇の皇子鐸石別命の裔の1人である清麿（清麻呂？）が、大功により和気朝臣を賜姓され、その子孫が内海氏を称した。