Oliver Ormond Gerard Michael MacDonagh, MA (National University of Ireland), MA, PhD (Cantab.), DLitt (Honoris Causa, Flinders University, Sydney University and National University of Ireland), BL (King's Inns, Dublin), FBA, FAHA, (Hon) MRIA, (1924–2002), was a noted professor of Irish history who made a particular study of the historic relationship between Ireland and the United Kingdom. MacDonagh spent most of his academic career at Universities in Cambridge, Adelaide, Cork and Canberra.