Qing Dynasty nobility

The Qing dynasty (1644–1912) of China developed a complicated peerage system for royal and noble ranks.

In principle, titles were downgraded one grade for each generation of inheritance.

Occasionally, a peer could be granted the privilege of shixi wangti (世襲罔替; shìxí wǎngtì; "perpetual heritability"), which allowed the title to be passed down without downgrading. Throughout the Qing dynasty, there were 12 imperial princely families who enjoyed this privilege. They were known as the "iron-cap princes".

The noble titles were inherited through a system of loose primogeniture: The eldest son from the peer's first wife was usually the heir apparent, but inheritance by a younger son, a son of a concubine, or brother of the peer was not uncommon. Non-heir sons of imperial princes were entitled to petition for a lower title, according to his birth (by the chief consort, secondary consort or concubines) and his father's rank, than the one they would have received had they been the heir. Non-heir sons of other peers were also occasionally granted a lower title.

Whether imperial or not, the inheritance or creation was never automatic, and must be approved either by the Emperor, the Ministry of Personnel, or the Imperial Clan Court. Imperial princes, upon reaching adulthood at the age of 20, must pass tests in horse-riding, archery and the Manchu language before they were eligible for titles. Imperial princesses, other than the Emperor's daughters, were usually granted titles upon marriage, regardless of age. Princesses' titles were also usually fixed after they were granted, and were not affected by changes in their fathers' nobility ranks.

Yunjiwei ("sub-commander of the cloud cavalry") was originally a military rank created in the Sui dynasty, but it was later turned into a military honour in the Tang dynasty as part of the xun guan (勳官; xūn guān) system. The Qing dynasty abolished the separate military honour system and merged it into the nobility rank system, using yunjiwei as the lowest grantable rank of nobility, and the basic unit of rank progression.

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