In Orzammar, dwarven society is divided into rigid castes with houses that compete for power and prestige. But all that is discarded when a dwarf abandons the Stone for the surface. Under the open sky, everyone is equal. Or so the story goes.
The truth is that thousands of years of tradition are not so easily tossed aside. Even though surface dwarves are officially stripped of their caste, many maintain a hierarchy among themselves along the old caste lines. Formerly noble houses are accorded more respect than casteless brands who come up in search of opportunity. The poorest "noble" dwarf on the surface looks upon the rich "lower caste" dwarves with contempt.
Upper-class surface dwarf society is roughly divided into two camps: kalnas, who insist on maintaining caste and rank (typically those from the Noble or Merchant Caste families) and ascendants, who believe in leaving Orzammar's traditions underground and embracing life in the sunlit world.
Maintaining some tie to Orzammar was seen for generations as the only lifeline for surface dwarves. Bringing surface goods to their kin underground and lyrium and metals to the surface was not only the most lucrative means of making a living, but also a sort of sacred duty, as many surface dwarves willingly accepted exile and the loss of their caste to better serve their house or patron. In recent years, many surface dwarves, particularly ascendants, have branched out. They started banks, mercenary companies, and overland trade caravans. They became investors and speculators in purely surface trade. These new industries have proven tremendous sources of wealth, but are looked down upon by their more conservative kin.
For less-affluent surface dwarves, association with a powerful kalna can open many doors. They can get credit with dwarven merchants and are offered work opportunities by the powerful Dwarven Merchants' Guild more readily, sometimes, than more qualified but less-connected individuals.
—From The Dowager's Field Guide to Good Society, by Lady Alcyone