A Diem refers to both an official role and common practice within the Capellan Confederation. Officially, a diem is an administrative office, though it may also be considered a type of unofficial nobility (one that is nevertheless traditionally filled by a noble or formerly noble family). Diems are appointed on behalf of a Duke or Duchess to oversee the administration of a warren, a subdivision of their duchy. Diems also have the power to appoint rulers for individual demesnes within their warren.
Additionally, a diem may refer to any nobleman who has been hired by another to run their fiefdom in absentia while they are away at court on Sian. Utilized by those nobles who can afford it, many demesnes, warrens, and even duchies are administered by diems on behalf of their nominal liege-lords; often a noble will go for years without stepping foot inside their own fiefdom.
- House Liao (The Capellan Confederation) , p. 60-61
- Handbook House Liao, p. 98