This study describes John's origins in Cornwall, his years in Oxford, his life as vicar of berkeley in gloucestershire and his association with the Berkeley family. At the same time it provides a cultural history of 14th-century England ranging from the administrative, geographical and linguistic status of cornwall, to the curriculum of a medieval university.This study combines a cultural history of 14th-century England with a biography of Trevista, from his Cornish origins, through his years in Oxford to his life as vicar of Berkeley, Gloucestershire, and his association with the Berkeley family.