Mac Fhirbhisigh was most likely born at the family castle, in the parish of Lackan, Tireragh, County Sligo, sometime in the first quarter of the 17th century. He was originally known as Dubhaltach Og ("young … See more

In April 1656, Dubhaltach acted as a witness to his hereditary lord, Dathi Og O Dubhda (David O Dowd) upon his marriage to Dorothy O Down. He may have drafted the … See more

After the death of Sir James, Mac Fhirbhisigh may have travelled to Gort, seeking patronage from Diarmuid Ó Seachnasaigh (Sir Dermot O Shaughnessey), as … See more

There are no substantial surviving details of Dubhaltach's personal life. It is unknown whether he married or ever had children. His brothers were Padraig (fl. 1663), Diarmaid, and Seamus (fl. 1656) but no sisters are mentioned. Nor does he record the year his father … See more

The first certain date that can be associated with Dubhaltach is 5 May 1643, when he was situated at Ballymacegan translating the ancient glossary Duil Laithne ("the book of Latin"). In that year he transcribed from an old Mac Aodhagan manuscript what is … See more

During 1665 and 1666, Dubhaltach was employed in Dublin by Sir James Ware, providing him with English translations of parts of certain Irish tracts. These included extracts from the See more

According to Ruaidhrí Ó Flaithbheartaigh – as noted by Edward Lhuyd – Dubhaltach's manuscripts were passed on his death to his lord, David O Dowd. Ó Flaithbheartaigh himself obtained Dubhaltach's transcript of Chronicum Scotorum. … See more