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"
Yarn Market, Dunster on the motte by the start of the 12th century, and the castle survived a siege during the early years of the Anarchy. At the end of the 14th century the de Mohuns sold the castle to the Luttrell family. Dunster had become a centre for woollen and clothing production by the 13th century, with the market dating back to at least 1222, and a particular kind of kersey or broadcloth became known as 'Dunsters'. The prosperity of Dunster was based on the wool trade, with profits helping to pay for the construction of the tower of the Priory Church