History has been offered as part of the curriculum for all students in Mary Immaculate College since its opening in 1901. For the first twenty years the main concentration was on British and Imperial history. After independence the emphasis was placed on Irish history taught from a strongly nationalist viewpoint. The major developments in Irish historical research from the late 1930s onwards appear to have been acknowledged if not always welcomed as the following vignette from the College Annual of 1943 shows:
'The Two St. Patricks: One of the outstanding features of the first term was a lecture given by Fr. John Ryan, S.J., on the above subject. We were already acquainted with Professor O’Rahilly’s theory regarding the "Two Patricks", a theory which I must say was received with great indignation by all the students of Mary Immaculate. We were charmed to find that Fr. Ryan had undertake to disprove the learned Professor’s theory. After the lecturer spoke so lucidly we were all gladly convinced that there was but one St. Patrick, the Saint whom we were taught to revere since childhood, as the patron saint of Ireland. The applause that greeted Fr. Ryan, as he left Our Lady's Hall was a token of how we had appreciated his lecture. Then with all the earnestness of our hearts, we sang "Hail! Glorious Saint Patrick".'
Under the two year teacher training course which the College offered for the first seventy five years of its existence, History remained a core subject with an equal emphasis on its academic integrity and the appropriate methodology required for the primary school. The academic linkage with University College, Cork in 1974 and the introduction of a three year degree programme led to the creation of a distinct History Department.
Brid Cahill, who had held the main responsibility for the subject since the early 1970s was joined by two distinguished Cambridge graduates, Dr. Brendan Bradshaw and Dr. Tom Dunne. Courses on British, European, American and World history were introduced in addition to a major re-organisation of the Irish history curriculum both in content and methodology. Further staff changes were to follow with the departure of Tom Dunne to U.C.C. and the return to Cambridge of Fr. Bradshaw. Dr. Chris O’Mahony from T.C.D. joined the Department for two years while Liam Irwin arrived from U.C.C. in 1977. Dr. Maura Murphy was appointed in 1979 after completion of her doctoral studies at the University of Leicester. Brid Cahill relinquished the position of Head of the Department later that year and was replaced by Liam Irwin. Dr. Dympna McLoughlin, Dr. Declan Downey and Dr. Bernadette Whelan held contract posts in the Department in the 1980s and early 1990s.
Dr. Úna Ní Bhroiméil, Dr. Deirdre McMahon and Dr. Liam Chambers took up positions in the later 1990s and early 2000s. Having guided the Department for more than 30 years, Liam Irwin retired in August 2011. Dr McMahon retired in August 2017. Dr Clodagh Tait, Dr Cathy Swift and Dr Brian Hughes joined the department in recent years.