 Appointed lecturer at Manchester in 1962, he was then invited, aged 36, to become the first Professor of History at University of York.In 1979, he returned to Oxford as Master of St Peter's College, presiding over an improvement in academic performance at the college, increased endowment and building extensions before retiring in 1991.He remained an active publisher for the remaining nine years of his life before dying in hospital following what appeared to be routine surgery.