James Francis Lydon, (born 1928), was an Irish historian, Lecky professor of History at Trinity College Dublin.
The tenth of eleven children of a Catholic family, his father was a baker and his mother a native Irish specker. Both of their families were from Connemara. They ensured that all of their children received secondary and third-level eductation.
Lydon studied English and History at University College Galway (now National University of Ireland, Galway). He graduated in 1950 with first-class honours, staying on to undertake research for a master's degree. His teacher, history department professor Mary Donovan O'Sullivan "suggested that Ireland's contribution to the military activities of the English crown in the thirteenth century might be a subject that would repay investigation." He moved to London to undertake his research.
In 1955 he completed this thesis - Ireland's participation in the military activities of English kings in the thirteenth and fourteenth centuries, and having a full year left on his Travelling Fellowship in the National University of Ireland, he was advised by mentor Sir Maurice Powicke to "use the residue of the funding to travel on the continent, ... stay clear of archives ... read, visit galleries, listen to music, meet people and generally lift his eyes beyond the confines of the Record Office in Chancery lane." This experience "gave him an appreciation of European 'culture' in its broadest sense..." and enabled "... Lydon to bring the histroigraphy of late medieval Ireland to maturity." Returning to Galway in 1956 he taught history via Irish and English and in 1959 moved to Dublin to lecture at Trinity College Dublin. In October 1980 he succeeded A.J. Otway-Ruthven as Lecky professor of History, a post he held till his retirement in 1993.
All quotes from pages 48 and 49 The Lecky professors, in op.cit.