A Thegn is the ruler of one of the major island territories of Asnorland. Thegns stand below the Stadtholder and above the Jarls who govern smaller districts, towns, and local territories. The office combines noble status with substantial regional sovereignty: a Thegn normally controls an island-level court, revenues, military resources, patronage networks, and relationships with subordinate Jarls.
Thegndoms are usually hereditary in practice, but inheritance alone does not make succession unchallengeable. An obvious and capable heir normally succeeds without difficulty because continuity benefits both the ruling family and its followers. A disputed, weak, very young, absent, or widely hated heir may instead face rivals who argue that the line has failed to produce someone worthy of recognition.
Each Thegn is also traditionally the Jarl of the principal Jarldom associated with the seat of the Thegndom. No Thegn other than the Stadtholder is ordinarily permitted to hold more than one Thegndom. The Stadtholder is the exception because the office carries both Inis Faerna and the historical claim to Inis Cailean.
The Thegns are central to national politics because the Stadtholder cannot treat them as ordinary provincial officials. Their support is necessary for a formal challenge to the Stadtholdership, and their willingness to provide troops, ships, supplies, or money determines how much military strength the kingdom can bring to bear in a major war. The different islands possess different resources, so individual Thegns may derive influence from trained armies, farmland, mineral wealth, merchant fleets, fortified ports, or especially loyal networks of Jarls.