Kenneth Bruce McFarlane, FBA (18 October 1903 – 16 July 1966) was one of the 20th century's most influential historians of late medieval England. He was born on 18 October 1903 and was the only child of A. McFarlane, OBE. His father was a civil servant in the Admiralty and the young McFarlane's childhood was an unhappy one. This may have led to the deep melancholy that seemed to pervade much of his adult life. His family sent him to public school at Dulwich College as a "day-boy." McFarlane did not particularly like the atmosphere of the public school. In 1922 he earned a scholarship to read history at Exeter College Oxford. His tutor during these years was C. T. Atkinson. Following the completion of his DPhil on the loans of Cardinal Beaufort to the English Crown (September 1927), McFarlane became a fellow of Magdalen College, where he remained for the rest of his life. Many of his colleagues and students found him difficult to approach, but to those who could break through the facade he became a great and true friend. McFarlane also found, through the help of his great friend Dr. Helena Wright and her family, a home and a family of sorts. In Wright's house he found that he could be himself and find refuge from the daily grind of the University and a place of joy. McFarlane never married.
His most important contribution to the field was his revision of the understanding of late medieval feudal relationships, known as "bastard feudalism". The old consensus, promoted primarily by Bishop Stubbs, was that payment for service in feudal relationships had promoted greed and civil strife. McFarlane, however, pointed out the adhesive effect of such a system, and other forms of patronage, as a field of common interest for the crown and the landed . According to Christine Carpenter in, "Wars of the Roses - Politics and the constitution in England c1473-1509” Cambridge University Press 1997: "It is hard to exaggerate the impact of McFarlane’s work, especially at Oxford where he taught. A whole generation of students there was inspired to work on what had been a very neglected century; nearly all the political historians of fourteenth and fifteenth century England today, including the present writer, are, academically speaking, the children or grandchildren, even great grandchildren, of McFarlane" She also described him as being responsible for a "paradigm shift".