John Tupper Saywell (born 1929) is an eminent Canadian historian specializes in the fields of politics and constitution. Saywell received his B.A. and M.A. from University of British Columbia and his Ph.D. from Harvard University. He taught at University of Toronto and York University. He was the author of The Office of Lieut.-Gov. 1957; The Canadian Journal of Lady Aberdeen 1960: Lord Minto's Canadian Papers 1983; Making the Law 1991; Just Call Me Mitch 1991.
J.T. retired from all teaching responsibility at York University in 1999.