twelve level cap and rank system
Historical term for the first Japanese court rank system, established in 603 CE by Prince Shōtoku. Used in discussions of early Japanese state formation.
The twelve level cap and rank system was established in the era of Empress Suiko.
From 冠位 (cap rank) + 十二 (twelve) + 階 (rank, level). The term refers to the system of twelve ranks indicated by the color of official caps.