Canon Sheehan of Doneraile places the action of the song in the Williamite wars of 1689-91, but according Donal O'Sullivan in Songs of the Irish "John O'Dwyer of the Glen" was the third son Darby O'Dwyer (died 1629)who was chief of the O'Dwyers of Kilnamanagh and lived at Cloniharp Castle near Dundrum Co. Tipperary. The glen referred to is supposed to be the Glen of Aherlow. Little is known of his history but his cousin Colonel Edmund O'Dwyer operated in Tipperary, Limerick and Waterford against the Cromwellian forces in the period 1649-1652. This may possibly be who Canon Sheehan had in mind even though he placed him in the "wrong war".