William de Mohun of Dunster, 1st Earl of Somerset William de Mohun of Dunster, 1st Earl of Somerset William de Mohun of Dunster, Earl of Somerset (c. 1090 – c. 1155), 2nd feudal baron of Dunster, was a favourite of Empress Matilda and a loyal supporter of her in the war against King Stephen, during which he earned the epithet of the "Scourge of the West". William was the son of William de Moion, who was seigneur of Moyon which is close to Saint-Lô. The elder William was High Sheriff of Somerset in 1084. During the war between Matilda and Stephen, Stephen marched against Mohun's castle at Dunster, but
Feudal barony of Dunster was Principle Private Secretary to the Governor-General of Australia. In 1918 he married Alys Anne Bridges (died 1974), daughter of Rear-Admiral Walter Bridges, of Victoria, Australia, whom he had met in Australia. After his marriage he returned to England with his wife, and moved into Dunster Castle, which had been given them by his father, who continued to live at East Quantoxhead. Although not a player himself, he was interested in Polo and established a polo ground with stables at Dunster, and hosted tournaments. During World War II he was vice-chairman of the Great Western Railway Company and during the