There were three main feudal social groups in Tibet prior to 1959, namely ordinary laypeople (mi ser in Tibetan), lay nobility (sger pa), and monks.
The Tsangpa Dynasty (1565-1642) and Ganden Phodrang (1642-1950) law codes distinguished three social divisions: high, medium and low.
Nobles, government officials and monks of pure conduct were in the high division, only – probably – the Dalai Lama was in the very highest position.
[3] Anthropologists have presented different taxonomies for the middle social division, in part because they studied specific regions of Tibet and the terms were not universal.
[4][5][6][7] Both Melvyn Goldstein and Geoff Childs however classified the population into three main types:[8][9] In the middle group, the taxpaying families could be quite wealthy.
[11] Membership to each of these classes was primarily hereditary; the linkage between subjects and their estate and overlord was similarly transmitted through parallel descent.
[14] The treba (also tralpa or khral-pa) taxpayers lived in "corporate family units" that hereditarily owned estates leased from their district authority, complete with land titles.
Their primary civil responsibility was to pay taxes (tre-ba and khral-pa means "taxpayer"), and to supply corvée services that included both human and animal labor to their district authority.
The householder class (du-jung, dud-chung-ba[9] duiqoin, duiqion, düchung, dudchhung, duigoin or dujung) comprised peasants who held only small plots of land that were legally and literally "individual" possessions.
Ragyabpa were also divided into three divisions: for instance a goldsmith was in the highest at third feudal class, and was not regarded as being as defiled as an executioner, who was in the lowest.