Peter Hayes Sawyer (born 25 June 1928) is a British historian of Medieval England who is known for his annotated catalogue of Anglo-Saxon charters. Anglo-Saxon charters are referenced by "Sawyer" numbers (abbreviated 'S' as for example in charter "S407") according to his catalogue.
Sawyer was born in Oxford, England on 25 June 1928, and studied at Oxford University from 1948 to 1951. Sawyer taught at the University of Leeds from 1964, becoming Professor of Medieval History in 1970. He retired early from Leeds in 1982 and was subsequently (in 1998) given the title Emeritus Professor. Sawyer continued his teaching and research at Göteborg University as a docent. Between 1996 and 2006 he worked in Trondheim (where his wife was a Professor of Medieval History), connected to NTNU, and from 2006 he is living and working in Uppsala (Sweden).