Feudal barony of Dunster of Dunster, was as follows: William de Moyon (died post 1090) ("alias" de Moion, later de Mohun), Domesday Book holder of Dunster Castle, 1st feudal baron of Dunster, was Seigneur of Moyon near Saint-Lô in Normandy and was Sheriff of Somerset in 1086. He was the founder of the English "de Mohun" family, prominent in the Westcountry, extinct in the male line seated at Dunster in 1375 and extinct in the junior male line seated at Mohuns Ottery in Devon at about the same time. He is recorded in the Domesday Book of 1086 as holding the manor of "Torre"
Dunster to the castle were undertaken by Henry Fownes Luttrell who had acquired it through marriage to Margaret Fownes-Luttrell in 1747. Following the death of Alexander Luttrell in 1944, the family was unable to afford the death duties on his estate. The castle and surrounding lands were sold off to a property firm, the family continuing to live in the castle as tenants. The Luttrells bought back the castle in 1954, but in 1976 Colonel Walter Luttrell gave Dunster Castle and most of its contents to the National Trust, which operates it as a tourist attraction. It is a Grade I