SOMERSET. This is one of the few instances of a surname having been borrowed from a title. Henry Beaufort, third Duke of Somerset (great-grandson of John of Gaunt), who was beheaded in MG3, for his adherence to the cause of King Henry VI., left issue a natural son. Sir Charles Somerset, Knight of the Garter. He was elevated to the peerage, and his lineal descendant, Henry Marquis of Worcester, was created Duke of Beaufort in 1G82. Thus, in the same blood, the surname and the title have changed places, and instead of Beaufort, Duke of Somerset, we have Somerset, Duke of Beaufort.

Lower, Mark A (1860) Patronymica Britannica: a dictionary of the family names of the United Kingdom. London: J.R. Smith. Public Domain.