Born Cú Coigriche mac Tuathal Ó Duibhgeannain, presumably about or after 1590, his name was Latinized to Pereginus (anglicized Peregrine) when he took holy orders in the Franciscan Order based at Leuven. Cú Coigriche (also Cuchogry) means "hound [or hero] of the neighbouring[or foreign] land." His family, the Clan Uí Dhuibhgeannain, were professional historians from Annaly many of whom had crossed the Shannon and practised their art in Connacht. Here the Ó Duibhgeannains set up a bardic college at Kilronan, near Lough Key in northern Roscommon.
Nothing is known of his life and activities until he began work with Cú Choigriche Ó Cléirigh and Fearfeasa Ó Maoilchonaire under the direction of Brother Mícheál Ó Cléirigh about 1627. In that year Ó Cléirigh was sent from his mother house at Leuven to Ireland to collect Irish literary, historical and chronological material in danger of being lost. These material were assembled into a number of compilations, the most famous being the Annals of the Four Masters.
Nothing is known of his life after 1636, the year the annals was completed. It is entirely likely that he returned to Leuven with Brother Michael. However, a slight possibility exists that he remained in Ireland, as a copy of the annals was being used in the town of Galway by Dubhaltach MacFhirbhisigh in the late 1640s. It may not be coincidental that a kinsman of Ó Duibhgeannain, Daibhidh Ó Duibhghennain living and working in Connemara at least as early as 1651. More than this cannot with certainty be said.