Breton literature may refer to literature in the Breton language (Brezhoneg) or the broader literary tradition of Brittany in the three other main languages of the area, namely, Latin, Gallo and French – all of which have had strong mutual linguistic and cultural influences.
Old and Middle Breton literature 
Breton literature can be categorised into an Old Breton period, from the 5th to 11th century; and a Middle Breton period, up to the 17th century. The period break is marked by the Norman invasions of the 10th and 11th centuries which triggered an exodus out of Brittany. Many Old Breton extant words are glosses in Latin manuscripts from the 9th and 10th centuries, now scattered in libraries and collections throughout Europe. It is likely there was a highly developed oral tradition during the Old Breton period. And on the evidence of Breton names, it would appear that Old Breton literature inspired much of Arthurian literature, the story of Tristan and Iseult and the romances of Chrétien de Troyes.
Leyden Manuscript 
The oldest surviving manuscript in the Breton language (dating to the end of the 8th Century) is kept in Leyden University, Netherlands, and predates by more than a century the oldest text referenced in French. It is generally assumed by specialists that this is the most ancient text in a continental Brythonic language and was studied by the late Professor Léon Fleuriot (1923–1987). The manuscript itself is a fragment of medicinal recipes composed of plants suggesting that Breton may well have been used by people of learning at the turn of the 11th century.
The Breton Gospel 
Although written in Latin the Breton Gospel (British Library, Egerton 609) is an important literary work in terms of the wider scope of Breton culture. Amongst other things it attests to a high degree of learning and, presumably, monasterial wealth in Brittany comparable to that of Lindisfarne and Kells. The Gospel Book manuscript dating from the 9th century contains the Latin text of the four Gospels, along with prefatory material and canon tables – an interesting admixture of traditions. The Breton Gospel is similar to the form of Carolingian minuscule developed at Tours – one of the classicising centres of the Carolingian Renaissance, and although the form of the large illuminated letters that form the beginning of each Gospel are comparable to those found in Carolingian manuscripts, the decoration thereof is far more similar to insular manuscripts such as the Book of Kells and the Lindisfarne Gospels, suggesting a continuum of cultural tradition. However, the decoration here is simpler and more geometric in form than that to be found in insular manuscripts. The beginning of each Gospel is preceded by a full miniature of the appropriate Evangelist's symbol and the vellum folios themselves measure 32.5 by 23 centimetres.
Another early known piece of Breton literature is found in the margins of a 14th century Latin manuscript, scribbled by a scribe weary of his toil and mind on more immediate concerns, he left for posterity a four line love poem, the first two lines beginning:
- An guen heguen am louenas
- An hegarat an lacat glas
- The fair one, her cheek gladdened me
- The lovable one of the blue eye.
Breton poetry 
The main principle of Breton poetry is that the next to last syllable in a line should rhyme with one or more other syllables in the same line. For example in the first line above, "en" is the second to last syllable, which rhymes with "guen" and "heguen". In the second line, "at" is the second to last syllable which rhymes with "hegarat".
There are several texts from the 15th and 16th century:
- Destruction of Jerusalem, fragments.
- Life of Saint Guénolé, fragments.
- Dialogue Between Arthur and Guynglaff, a very badly damaged 247-line poem passed down through multiple generations of copies.
- Life of Saint Nonn and Her Son Devy
- Buhez Sante Barba ("The Life of Saint Barbara"), a mystery play on the life and miracles of Saint Barbara.
Modern literature 
Before the literary revival movement promoted by Gwalarn in the early 20th century, most literature in Breton consisted of religious writings.
Jean-François Le Gonidec (Breton: Yann-Frañsez ar Gonideg) (1775 - 1838) played an important role in Breton literature by initiating a reform of Breton orthography, producing an orderly grammar and making the first Breton translation of the New Testament.
Prose writings in Breton, almost exclusively religious, start appearing from the 17th century. The second half of the 18th century saw the appearance of the first secular works in Breton: Ar Farvel Goapaer by François-Nicolas de Pascal de Kerenveyer and Sarmoun great war ar maro a Vikael Vorin by Claude-Marie Le Laë. Most literature remained oral, however.
19th century 
In the 19th century antiquarians and Celtic revivalists undertook the collection of folk texts, songs and stories. The wave of interest in collecting oral traditions reached Brittany around 1815-1820 when educated members of the gentry such as Aymar de Blois de La Calande, Barbe-Émilie de Saint-Prix, Jean-Marie de Penguern, Jean-François de Kergariou, Ursule Feydeau de Vaugien, exchanged their findings informally. Writers such as Anatole Le Braz and Théodore Hersart de la Villemarqué (son of Ursule Feydeau de Vaugien) brought new readers to traditional Breton literature.
Barzaz Breizh, the "Ballads of Brittany", (literally, barzaz Breizh = bards of Brittany) is a collection of Breton popular songs collected by La Villemarqué and published in 1839 (revised and expanded edition 1845). It was compiled from oral tradition and preserves traditional folk tales, legends and music. Although hugely influential, La Villemarqué's work came under attacke from a later generation of collectors for having edited his materials in accordance with the demands of contemporary literary taste. Taking a more rigorous approach to the collection of oral material, François-Marie Luzel published Gwerziou Breiz Izel (1868-1874) and Contes Bretons (1870).
Auguste Brizeux used Le Gonidec's standardised Breton for Telenn Arvor (1844), and his collection of proverbs, Furnez Breiz (1845).
20th-21st centuries 
In the 1920s a movement, in which the linguist and author Roparz Hemon played an important part, arose to introduce the trends of modern literature into Breton. The literary magazine Gwalarn provided an outlet for modern authors, such as Jakez Riou and Yves Le Drézen (who published the first long novel in Breton in 1941). The artistic movement Seiz Breur included writers.
Pierre-Jakez Hélias (1914–1995) wrote prose and poetry in both Breton and French. His contemporary Añjela Duval (1905–1981) wrote poetry reflective of her peasant origins, mysticism, and social conscience.
In contrast to the concentration on short-form writings in Breton which had dominated production in the previous century, a trend towards novel-length writing developed from the 1980s. By the beginning of the 21st century a dozen or so novels on average were being published in Breton every year. The choice of genres was diverse, including detective fiction, historical fiction and autobiographies. With incentives from educational contexts, contests and literary prizes, there has been a development of young-adult fiction, often using fantasy and science-fiction themes. Yann-Fañch Jacq is a notable author of such fiction aimed at young Breton-speaking readers. New more adult themes have appeared as the novel genre has developed: for example, Yann Fulub Dupuy's Par Dibar (2006) deals with sexuality.
Prizioù is an annual (since 1997) award for expressions of Breton culture in seven categories, of which fiction is one. Prix Xavier de Langlais (named after Xavier de Langlais) is an annual (since 1976) prize for best unpublished prose work or poetry collection.
See also 
- Gibson & Griffiths (2006). The Turn of the Ermine. London: Francis Boutle. ISBN 1903427282.
- Parlons du breton!. Rennes: Ouest-France. 2001. ISBN 2737329272.
- FAVEREAU, Francis. "Quand le breton se met au roman". Langues et cité 17. Délégation générale à la langue française et aux langues de France. Retrieved 25 August 2012.
- British Library catalogue entry (in Latin)
- British Library Collect Britain illuminated manuscript virtual exhibition