By the Yakusa no Kabane (the eight honorary titles) reform by the Emperor Tenmu, the kabane of Omi was demoted to the sixth highest, and afterwards Ason (or Asomi) became the kabane title for influential clans.
天武天皇の八色の姓の改革により、臣の姓の地位は上から6番目に格下げとなり、その後は朝臣が、有力氏族の姓となっていく。