Robert Dunlop was a notable historian of Ireland, and was one of the first to bring the methods of modern scholarship to the study of Irish history.
Dunlop was born in Manchester, but grew up in Southport, Lancashire. He attended Owens College between 1879 and 1882, and took an honours degree in history. He then pursued research and was a Bishop Berkeley fellow at Owens between 1888 and 1890. In 1890, Dunlop married Elisabeth Waagner, the daughter of a wealthy Austrian industrialist, and they had a son.
In 1908, he was made honorary special lecturer in Irish history at the University of Manchester. Dunlop lived in Austria for most of the year, but came to Manchester to deliver an annual courses of lectures. He also lectured for University Extension classes. On the outbreak of war in 1914, Dunlop was living in Austria, and was put under house arrest for the duration of the War. In 1920 he was reappointed a special lecturer in Irish history at Manchester, a post he held until his death. He returned to live in Austria in 1923, with the family fortunes much reduced.
Dunlop was known as an assiduous researcher, with a detailed understanding of Irish archives. His particular area of specialism was Ireland during the 16th and 17th centuries, and he edited a important collection of documents, Ireland under the Commonwealth (1913) based on his researches. He also had a great interest in the historical cartography of Ireland, and did much to advance this subject area. Dunlop was a prolific contributor to the Dictionary of National Biography, writing 169 articles on various Irish notables, and he contributed several essays to the Cambridge Modern History on Ireland in the 16th to 18th centuries, as well as an essay on modern Ireland. Much of his early research was presented in the English Historical Review, but he also published several monographs including The life of Henry Grattan (1889), Daniel O'Connell and the revival of national life in Ireland (1900), and Ireland from the earliest times to the present day (1922). His major work on Irish history, written during the 1920s, remains unpublished.
In the 1920s, Dunlop became increasingly interested in the contemporary politics of Central Europe, publishing articles on Austria and Czechoslovakia in the Contemporary Review and the Quarterly Review. On his death in 1930, fellow historian Edmund Curtis called Dunlop: "Our greatest authority on Modern Irish history from the sixteenth century onwards.”