The Imager Portfolio is a 12 book series of fantasy novels recently completed by American novelist L. E. Modesitt, Jr.
First Quaeryt is sent north to investigate and quell a rebellion, then he is sent to manage a recovery operation from a natural disaster as Lord Bhayar's Princeps, (book 5).
In book 7, Antiagon Fire, the battalion's increasing skill as imagers eventually prove pivotal to uniting the four fragmented kingdoms of Lydar into one country: Solidar.
In book 8, Rex Regis, Lord Bhayar consolidates the new empire, instituting the rule of law, accounting and standardized record keeping, while Quaeryt establishes the Collegium on Imagilse as a refuge for imagers.
In 406 A.L., the books Madness in Solidar and Treachery's Tools follow the efforts of one Alastar to revitalize the decadent Collegium and the ineffectual role that imagers now play in an increasingly restless society faced by rebellious High Holders and their wont to turn back time, returning Solidar to an earlier era when their status was at the apex of the social order.
Serfdom is the normal lot of peasants with few freemen (poor farmers), factors (merchants, traders) or crafters (skilled laborers).