What Was Korea's Bone-rank System?

Royal dragons could only be displayed by members of the sacred and true bone ranks
A royal dragon adorns this tile from Korea's Silla Dynasty. via Wikipedia

The "Bone-rank" or golpum system developed in the Silla Kingdom of southeastern Korea during the fifth and sixth centuries CE. The designation of a person's hereditary bone-rank signified how closely they were related to royalty, and thus what rights and privileges they had in society.

The highest bone-rank was seonggol or "sacred bone," made up of people who were members of the royal family on both sides.

Originally, only sacred bone-ranked people could become kings or queens of Silla. The second rank was called "true bone," or jingol, and consisted of people of royal blood on one side of the family and noble blood on the other.

Below these bone-ranks were the head ranks, or dumpum, 6, 5 and 4. Head-rank 6 men could hold the higher ministerial and military posts, while members of head-rank 4 could only become lower-level bureaucrats.

Interestingly enough, the historical sources never mention head-ranks 3, 2 and 1. Perhaps these were the ranks of common people, who could not hold government office and thus did not merit mention in government documents.

Specific Rights and Privileges

The bone-ranks were a rigid caste system, similar in some ways to India's caste system or feudal Japan's four-tiered system. People were expected to marry within their bone-rank, although higher-rank men could have concubines from lower ranks.

The sacred bone rank came with the right to assume the throne and to marry other members of the sacred bone rank. Sacred bone rank members were from the royal Kim family that founded the Silla Dynasty.

The true bone rank included members of other royal families that had been conquered by the Silla. True bone rank members could become full ministers to the court.

Head rank 6 people likely were descended from sacred or true bone rank men and lower ranked concubines. They could hold positions up to deputy minister. Head ranks 5 and 4 had fewer privileges and could hold only low functionary jobs in the government.

In addition to the career advancement limits imposed by one's rank, bone rank status also determined the colors and fabrics a person could wear, the area they could live in, the size of house they could build, etc. These elaborate sumptuary laws ensured that everyone stayed in their places within the system and that a person's status was identifiable at a glance.

History of the Bone Rank System

The bone rank system likely developed as a form of social control as the Silla Kingdom expanded and grew more complex. In addition, it was a handy way to absorb other royal families without ceding too much power to them.

In 520 CE, the bone rank system was formalized in the law under King Beopheung. The royal Kim family did not have any sacred bone males available to take the throne in 632 and 647, however, so sacred bone women became Queen Seondeok and Queen Jindeok, respectively. When the next male accended to the throne (King Muyeol, in 654), he amended the law to allow either sacred or true bone royals to become king.

Over time, many head-rank six bureaucrats grew increasingly frustrated with this system; they were in the halls of power every day, yet their caste prevented them from attaining high office. Nonetheless, the Silla Kingdom was able to conquer the other two Korean kingdoms - Baekje in 660 and Goguryeo in 668 - to create the Later or Unified Silla Kingdom (668 - 935 CE).

Over the course of the ninth century, however, Silla suffered from weak kings and increasingly powerful and rebellious local lords from head-rank six. In 935, Unified Silla was overthrown by the Goryeo Kingdom, which actively recruited these able and willing head-rank six men to staff its military and bureaucracy.

Thus, in a sense, the bone-rank system that Silla rulers invented to control the populace and firm up their own hold on power ended up undermining the entire Later Silla Kingdom.