Manuscript image of Isidore

Isidore and the origins of the Irish

Isidore of Seville, who died on 4th April 656AD, spans the classical and medieval worlds. Besides being bishop of Seville (from about 600 to his death), he also attempted to condense huge amounts of classical learning into his most famous work, the Etymologies. This huge reference work was very influential throughout the Middle Ages, and explains why Isidore was selected by Pope John Paul II as the patron of the internet. A good summary of Isidore’s life and of the Etymologies, including images from various manuscripts of the work, is available on the British Library website 1.

The importance of Isidore can be seen in the fact over a thousand manuscript copies of the Etymologies survive and it was one of the first printed books. Almost certainly available in all cultural centres by 800AD, it seems to have arrived particularly early in Ireland. The earliest fragments of the Etymologies is housed in St Gall (named for the disciple and companion of Saint Columbanus). Written in an Irish scribal hand, it may date back as far back as the mid seventh century. References in Irish texts show that the Etymologies was certainly known in Ireland by the late seventh century and by 700AD all but one of Isidore’s works had arrived in Ireland2.

Manuscript page of Etymologies
8th century manuscript of Etymologies, MSII 4856 Bruxelles
Isidore captured the Irish imagination. In particular the Etymologies broadened Irish knowledge of the Roman Empire and classical Latin literature and his treatise De rerum natura (on the nature of things) gave insight to classical cosmology and natural philosophy. They prized the new knowledge and Isidore, referring to him as “Issidir in chulmin (‘Isidore of the summit’, i.e. of the summit of learning)”3. His importance was also underlined by the claim in the Lebor Laignech (Book of Leinster) that the Etymologies came to Ireland from Spain in exchange for a manuscript of the great Irish epic, the Táin Bó Cúailnge4.

Isidore’s works impacted on Irish computus (the calculation of the date of Easter) and biblical commentaries. He was a major authority for natural philosophy, and the writer of Liber de ordine creaturarum (‘The Book of the Creatures’) not only cites Isidore, but wrote under his name. The use of etymologies in Irish law texts is probably as a result of Isidore’s influence. He was an authority for canon law, and was referenced in the Collectio canonum Hibernensis which collected together Continental canon law, scriptural and patristic excerpts, and Irish synodal and penitential decrees. He was also referenced in grammars, an important area for the Irish since they were not native speakers of Latin5.

The Auraicept na n-Éces (the scholars’ primer) which probably dates from the 7th century was one grammar which used the Etymologies. It also includes a defense of Irish (the earliest defense of the vernacular) which includes an account of the origins of the Irish language after the Fall of Babel. This was only one of the Irish origin stories which wove together classical and biblical threads.

Facsimile of folio 53 of the Book of Leinster, one of the sources for Lebor Gabála

The account of Irish origins found in a ninth-century Welsh manuscript, the History of the Britons, parallels the classic account of Lebor Gabála (The Book of Invasions). In that account the Gaels of Ireland are descended from Milesians who came to Ireland from Brigantia in Spain. John Carey argues that the details of this account are likely to derive from the works of (5th century Spanish historian) Orosius6. Others concur: “as Rolf Baumgarten has recently shown, the source of this legend is a reading of Orosius (I ii 71 and 80) in the light of Isidore (Etymologiae XIV vi 6)”7

Why would the Irish pick Spain? Isidore said Ireland lay between Spain and Britain citing Orosius (and other authorities of the time agreed) suggesting a possible direct link. Isidore also made the suggestion that “Hibernia” (Ireland) derived from the name for the Spanish peninsula “Iberia”: a link in names that could suggest a link in peoples. The importance of Isidore himself was another reason to think a connection between Ireland and Spain both plausible and desirable: “The seventh century was a time of intense and creative intellectual activity in Ireland, of a dynamic synthesis of native and imported concepts and traditions which was fundamental to the evolution of Gaelic culture. At just this time, links with Spain seem to have been close and important”8.

An analogous case is that of Irish genealogies. in the 1992 Carroll Lecture, Donnchadh Ó Corráin argued that the Irish genealogies were not created based on oral accounts. Instead they were entirely literary products, and were influenced by both Isidore and Orosius among others. For example, Irish genealogies place their earliest ancestor for Irish nobles at Japhet son of Noah, an idea that originated with Isidore. The genealogies came from writers for whom: “their ambience was christian Latin scholarship […], biblical history was their model, and Isidore their inspiration”9.

This linkage between Ireland and Spain via the Milesans had a long afterlife. It was developed from the seventh-century on reaching its final form in the eleventh century Lebor Gabála. It was used in Tudor times by Edmund Campion arguing for Stuart kingship over Ireland and by Edmund Spenser to support the colonisation of Ireland10 During the seventeenth century the supposed Irish-Spanish link was invoked to secure support from the Spanish crown, both for Irish scholars and military adventures. The Milesian story was included in Geoffrey Keating’s Foras Feasa ar Éirinn, which became the most popular account of Irish origins among both Catholics and Protestants in Ireland in the eighteenth century. It remained widely accepted into the twentieth century and still has a foothold among the general public today.

It is interesting that recent research on ancient DNA indicates that there was immigration from Spain: however it was 5,200 years ago in the Neolithic period. Genomes from two bodies dated 4,000 years old are different, bearing signs of ancestry in the Pontic Steppe (Russia and Ukraine) and also showing close genetic affinity with modern Irish, Welsh and Scottish. The genetic evidence suggests that Irish Gaels were not Milesians11.

Despite that, the imaginative history of seventh-century writers is still important. Though the works of Isidore and others, writers in early Christian Ireland created links between Ireland, and the biblical and classical world, that endured in ways they could never have imagined. The effects of that creative act still resonate today; a product of Ireland’s first knowledge economy built on imports from Europe.

Manuscript image of IsidoreFeatured Image: Isidore. Crop of image from the 10th century manuscript Maestro del Codex 167. Wikimedia, GNU Free Documentation License.

Further Reading

Paul Rincon (2015) “Ancient DNA sheds light on Irish origins” BBC News (28 Dec 2015).

John Carey (2001) “Did the Irish come from Spain?” History Ireland, Vol. 9, issue 3 (online)

Donnchadh Ó Corráin (1997) “Creating the past: the early genealogical tradition”, Chronicon 1 (1997) 2: 1-32 (online).

Marina Smyth (2016) “Isidorian Texts in Seventh-Century Ireland” in Andrew Fear and Jamie Wood (eds) (2016) Isidore of Seville and His Reception in the Early Middle Ages: Transmitting and Transforming Knowledge, Netherlands University Press, pp. 131-158.


  1. Nicole Eddy and Mary Wellesley (2016) “Isidore of Seville’s Etymologies: Who’s Your Daddy?” on British Library (website)
  2. Stephen A. Barney (trans.), W. J. Lewis (trans.), J. A. Beach (trans.) and Oliver Berghof (trans) (2006) “Introduction” in The Etymologies of Isidore of Seville, Cambridge University Press, pp. 24-5.
  3. Ó Cróinín (2005b), pp. 390-1.
  4. Luned Mair Davies (2006) “Isidore of Seville, St.” in John T. Koch (ed) Celtic culture: a historical encyclopedia. Vol. 1, ABC-CLIO, pp. 1025-6.
  5. Davies (2006).
  6. Davies (2006). John Carey (2001) “Did the Irish come from Spain?” History Ireland, Vol. 9, issue 3 (online).
  7. Donnchadh Ó Corráin (1997) “Creating the past: the early genealogical tradition”, Chronicon 1 (1997) 2: 1-32 (online).
  8. John Carey (2001).
  9. Corráin (1997)
  10. Andrew Hadfield, “Briton and Scythian: Tudor representations of Irish origins”, Irish Historical Studies 28 (1993) pp. 390–395.
  11. Paul Rincon (2015) “Ancient DNA sheds light on Irish origins” BBC News (28 Dec 2015).
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