As the only child of two celebrated Oxford historians, one of whom (J. O. Prestwich) specialised in the twelfth century and the other (born Menna Roberts) in the sixteenth and seventeenth, it might be thought that there was something preordained about Michael Prestwich's decision to devote his academic career to study of the thirteenth and fourteenth centuries. Born in Oxford in 1943, he was educated at Charterhouse before reading history at Magdalen College Oxford, from which he graduated with first-class honours in 1964. He undertook research for his doctorate at Christ Church, where he was firstly Senior Scholar, then Research Lecturer, between 1964 and 1969. His D.Phil. thesis, supervised by George Holmes and entitled ‘Edward I's Wars and their Financing, 1294–1307’, was completed in 1968, and in the following year he was appointed to a lectureship in medieval history at the University of St Andrews, where he remained for the next ten years. it was during this time that he married Maggie Daniel, a fellow medieval historian who had studied under Maurice Keen at oxford. Their two sons Robin and Chris were born while they were still in Scotland, their daughter Kate after they had moved to Durham, where Michael was appointed to a Readership in 1979 and where he spent the remainder of his academic career.

Michael Prestwich's published work, which runs to nine books (six authored, three edited) and some thirty articles and essays over four decades, exhibits a remarkable thematic unity and consistency of approach. Based on the meticulous analysis of manuscript and printed primary sources, it has focused primarily on the century between 1250 and 1350 (and especially the reign of Edward I) and has explored above all the impact of war upon the development of late medieval government and consequently upon the consolidation of the English state in the late pre-modern period.