Sources vary about Bradwardine's early life before receiving his degree in 1321. His exact date of birth is unknown but sources point to a date between 1290 and 1300. His place of birth is also unknown but some sources point to it being near Chichester, Sussex, or Harfield. The first concrete sources of his do not appear until he received his degree in 1321 from Balliol College, Oxford. Thomas Bradwardine became a Fellow of Merton College in Oxford, and was awarded his B.A. in August 1321. Bradwardine stayed at Merton College until 1333, when he was appointed Canon of Lincoln, and in 1337 he was appointed the chaplain of St Paul's Cathedral. His involvement with the ecclesiastical began in September 1333, when he was made the Canon of Lincoln, it is less corroborated by sources but it is stated that Bradwardine may have been the Bishop of Durham between 1335 and 1337. It is rumoured that this move to Durham helped put him into contact with King Edward III, which would lead to his eventual appointment of Chaplain of Old St Paul's Cathedral in London.