The spread of Irish Christian influence on the continent of Europe has attracted surprisingly few Irish students. John Lanigan touched on many of its aspects with critical discernment in his Ecclesiastical history of Ireland; Fr. John Ryan devoted some of his earliest attention to it; William Reeves was alive to the importance of the subject; but, if we omit laudatory and worthless summaries by untrained enthusiasts, almost every other contribution of value was made by non-Irish writers.

Irish transportation to the English colonies during the interregnum has often been represented as an indictment of English policy. John Lynch, the Irish historian, who was driven into exile during the protectorate, writing shortly after the restoration, deplored that Irishmen had been torn from the arms of their wives and children by ‘civic vultures’, transported, and sold as slaves in the West Indies. Among more recent writers, though Bagwell and Gardiner point out that the transported Irish became, not slaves, but indentured servants, Prendergast criticizes the ‘English slave-dealers’ and asserts that ‘Ireland must have exhibited scenes in every part like the slave hunts in Africa’.