From BrWiki
A province is a medium geographical region that is regarded as a single political or cultural unit. Normally the regent (if any) in control of a province as its head-of-state is the one who has the greatest law holdings within its borders and has been invested as the province's regent. A regent can control multiple provinces as part of their domain or realm, directly or through vassalage.
Provinces are described by their terrain and by their level. The terrain effects movement, adventuring, and imposes limits on the maximum level that a province can reach. Level describes the prosperity, organization, importance, and population of a province.
