Mac Firbhisigh, Giolla Íosa Mór

Mac Firbhisigh, Giolla Íosa Mór (fl. c.1392–c.1417), historian and poet, was a hereditary ollamh or master of bardic learning in the west Sligo territory of Tír Fhiachrach, ruled throughout the middle ages by the O'Dowda (Ó Dubhda) chieftains. The head of the Mac Firbhisigh family (the surname was later anglicised as Forbes or Cruise), traditionally officiated as joint inaugurator to the O'Dowda chiefs, and in this capacity Mac Firbhisigh is sometimes referred to as a file or poet; but members of this family were principally renowned as antiquaries and genealogists from the time of Amlaimh Mór Mac Firbhisigh (d. 1138), described in the Annals of Tigernach as ollamh of Tír Fhiachrach in both seanchas (traditional history) and in filidheacht (the poetic art). Over the centuries the family accumulated a fine library of historical texts at their headquarters in Lecan, parish of Kilglass, barony of Tireragh, Co. Sligo, where they eventually erected a castle in 1560. Giolla Íosa Mór was scribe and compiler of two of the most famous manuscripts in their collection, an anthology of sagas known as the Yellow Book of Lecan, on which he was working in 1392, and which now survives only in fragmentary form, and a large historical miscellany, the Great Book of Lecan, compiled c.1397–1418 as a family heirloom. Among the contents of the latter manuscript are an extensive corpus of genealogies, two versions of the ‘Lebor Gabála’, or ‘Book of the Invasions of Ireland’, and a series of important Middle Irish texts: the ‘Banshenchus Érenn’, a catalogue of famous Irish women; the ‘Cóir Anmann’, an encyclopedia of historically significant Irish names; and the ‘Dindshenchus’, lore associated with various Irish places.

In addition to collecting and transcribing these older texts, Giolla Íosa Mór was himself the composer of a long verse catalogue, ‘Imda gablán do chloind Chuind’, listing all the landowning families of Tír Fhiachrach and eulogising the head of each clan, thus demonstrating that he, like his predecessor Amhlaimh Mór, was a learned versifier as well as historian. Giolla Íosa Mór, who was the son of Donnchadh, son of another Giolla Íosa Mór Mac Firbhisigh, was only distantly related to the more famous seventeenth-century genealogist An Dubháltach Óg Mac Firbhisigh (qv) (d. 1671), although it appears both branches of the family were associated with the school of bardic learning at Lecan. Curiously enough for the head of a family which produced more than one set of annals recording notable events in Irish history, there is no record of the date of Giolla Íosa's death. Incidental marginalia in the Great Book of Lecan demonstrate that it was mostly compiled during the reign of Ruaidhri O'Dowda (c.1380–1417), with a section added in 1418 by one of the auxiliary scribes. Another indication of the date at which Giolla Íosa worked is that the section on the genealogy of the O'Neill chieftains refers to Niall Óg O'Neill (qv), who reigned as king of Tír Eoghain 1397–1403. However, Giolla Íosa's long topographical poem ‘Imda gablán do chloind Chuind’, which is entered into the Book of Lecan partly in his own hand, addresses Ruaidhrí's successor, Tadhg O'Dowda, as the newly succeeding chief, indicating that the historian was still active in 1417. The direct line of descent from Giolla Íosa was continued down at least to the seventeenth century through his son, Tomás Cam Mac Firbhisigh.