Twelve Cap Rank System (冠位十二階)

The twelve cap rank system (kani-junikai) was a court rank system established January 14, 604.

Summary
The "Nihon Shoki" (Chronicles of Japan) gives the start date of the system and lists the twelve ranks.

In "Jogu Shotoku Ho-o Teisetsu," a biography of Prince Shotoku, the ranks are given as "Shaku Juniku, Daitoku, Shotoku, Dainin, Shonin, Dairai, XX Daishin, Shoshin, Daigi, Shogi, Daichi, Shochi."
(XX denotes omitted characters)

The section on 'Eastern Barbarians, Kingdom of Wa' (the ancient name for Japan), in the "Sui Shu" (Book of Sui), Volume 81, Liezhuan No.46, (the King of Wa is referred to as Tarashihiko, whereas the New Book of Tang calls him "...") states "...", showing that the system was known in Sui Dynasty China.

The "Nihon Shoki" makes no mention of who established the twelve cap rank system, but from a description in the "Jogu Shotoku Ho-o Teisetsu" that Prince Shotoku and SOGA no Umako 'together reinforced rule over the whole country,' it is believed that the system was a legacy of these two.

The system aimed to impose ranks on powerful clans and to appoint talented people, regardless of their clan or title, to government posts. It also sought to increase the Emperor's authority over powerful clans by having the Emperor directly appoint ranks. But the system was, as it were, in transition and the highest hereditary titles, such as O-omi and Muraji, were still placed above the rank of daitoku. There are many examples of courtly rank coinciding with the hereditary title level to which the person belonged (there are no examples of people with titles other than Omi and Muraji being awarded the rank of Daitoku, or of people below Suguri and Kashira being awarded the rank of Shotoku). Moreover, with a few exceptions, including ONO no Imoko, who played an active role as an envoy to Sui Dynasty China, there were few records of promotion up the ranks. Due to this, some people have the view that there were certain restrictions on giving courtly ranks depending on clan and rank.

The twelve cap rank system was established following lessons learned from the first Imperial envoy sent to the Sui Dynasty in 600. Considering the situation in east Asia in the 7th century, it was considered extremely necessary for Japan to open diplomatic relations with Sui.

It is said that the twelve cap rank system of Northern and Southern Dynasties was introduced via Kokuryo and Paekche.

The twelve cap rank system was the first such system established in Japan and, following various court system changes and many twists and turns, developed into the Ritsuryo court rank system.

Ranks and cap colors
The description in the "Nihon Shoki" of the establishment in 603 of the twelve cap rank system gives the names of twelve ranks but not the color of the caps corresponding to each rank. From the study of historical evidence, it is presumed, though it can not be affirmed, that the colors for the twelve ranks were as stated below. The following list gives the name of each rank and the color of each cap, from highest to lowest.

Daitoku (Greater Virtue) (deep purple)

Shotoku (Lesser Virtue) (light purple)

Dainin (Greater Charity) (dark blue)

Shonin (Lesser Charity) (light blue)

Dairai (Greater Courtesy) (dark red)

Shorai (Lesser Courtesy) (light red)

Daishin (Greater Sincerity) (dark yellow)

Shoshin (Lesser Sincerity) (light yellow)

Daigi (Greater Justice) (pure white)

Shogi (Lesser Justice) (off white)

Daichi (Greater Knowledge) (black)

Shochi (Lesser Knowledge) (grey)

Blue in ancient times was close to purple.

(However, the system was changed to using different shades to distinguish between 'Greater' and 'Lesser' after the twelve cap rank system had already been established.)

The system of cap ranks was introduced.
"Nihon Shoki," the twelfth month of 603

On the fifth day of the twelfth month, the system of cap ranks was introduced for the first time. The twelve ranks were Daitoku, Shotoku, Dainin, Shonin, Dairai, Shorai, Daishin, Shoshin, Daigi, Shogi, Daichi, Shochi, with silk fabrics of each color corresponding to the rank. The top of the cap was put together to form a pauch-like shape and the hem of the cap was where the head was placed. Only exception was that on New Year's day, the decoration was put on caps.
This decoration was called Uzu.'

Spring, the first month of 604, cap ranks were granted to subjects for the first time and there were differences of rank among subjects.

The "Nihon Shoki" does not mention specific colors. The different shades of colors were introduced after the promulgation of the Yoro Code. The 'colors' mentioned in the "Nihon Shoki" are believed to have been blue, red, yellow, white, and black corresponding to the five Confucian virtues (charity, courtesy, sincerity, justice, knowledge), which was based on the Wu Xing (Five Phases). As "toku" (virtue) governs the other five virtues, it is presumed that it was allocated 'purple' since that had been valued as the color of the sovereign (emperor) since the Han dynasty (Tenmonshi of "Kanjo" (Historical records of the Han Dynasty)).

It is questionable how the two shades of 'white' were distinguished.

The depictions of people in the murals of the Takamatsuzuka tomb are useful for information on clothing for the twelve cap ranks. It is presumed that the drawings of these human figures provide information on dressing customs from the latter half of the 7th century to the first half of the 8th century.

Changes to the cap rank system
The cap rank system was revised many times until it was replaced in 701 by the official rank system.

The first major revision was the thirteen cap rank system in 647.

In 649, it was revised to nineteen cap ranks. Based on the thirteen cap ranks, the extra ranks were made by dividing the middle ranks.

In 664, it was divided into still smaller pieces and revised to twenty-six cap ranks. These revisions are considered to be attempts to fit hereditary titles, such as O-omi, that had been left out of the twelve cap ranks into the hierarchy of the system. However, it is said that the O-omi continued to used the old caps.

In 685, twelve ranks for Princes and above, and forty-eight ranks for high-ranking officials were introduced.

Princes with the rank of Shinno and Shoo were also incorporated into the cap rank system.

In 701, the cap rank system was abolished and transferred to the Grand Council of the State based on the Ritsuryo codes. This new system was based on the forty-eight cap ranks, but the rank names were revised to ones that were easier to understand, such as Shoichii (Senior First Rank) and Jusanmi (Junior Third Rank). The number of ranks was also reduced from forty-eight to thirty.