Rev. John Leslie (1571-1671), Bishop of Clogher, established the Irish branch and lands of the Leslie family when he purchased Glasslough, in Monaghan, in the final years of his life. John Leslie’s career had taken him to London as the pastorate of St. Martin’s-in-Victory, to Orkney as Bishop of the Isles, and to Ireland as the Bishop of Raphoe, located in the province of Donegal. Upon arriving in Raphoe in June of 1633, he recovered the church lands from the hands of secular usurpers through legal means. It was here in Raphoe that Leslie built a fortified palace, and defended the episcopal lands and Protestants during the rebellion of 1641, thereby earning his nickname, “The Fighting Bishop.” Leslie remained in Ireland during the Cromwell interregnum, but promptly displayed his loyalty to the monarchy upon Charles II’s ascension. In the post-Cromwell era, Leslie was restored to the See of Raphoe and later given the Bishopric of Clogher.