In 684, he enacted the Yakusa no Kabane (the eight honorary titles) so as to establish the order of social status within the imperial court, and put the new system indicating court ranks by headgear colors in effect and made Imperial Princes able to gain court rank.
さらに天武13年（684年）、八色の姓を制定して朝廷の身分秩序を確立し新冠位制を施行して冠位賦与を親王にまで拡大した。