Isidore of Seville (c.560–636), archbishop. Born at Seville of a noble family from Cartagena, Isidore was educated mainly by his brother Leander, a monk, but did not become one himself. From this monastic formation he acquired and communicated an encyclopedic knowledge in his books, which became most influential in medieval clerical and monastic education. His importance as archbishop was also considerable. He ruled for thirty-six years, succeeding his brother Leander, and energetically completing his work of converting the Visigoths from Arianism and organizing the Church in Spain through synods and councils. The most notable were the councils of Seville (619) and Toledo (633), over both of which he presided in person; one of their achievements was the decree (centuries before Charlemagne's similar one) that a cathedral school should be established in every diocese. Besides being a successful and influential educator, Isidore completed the Mozarabic missal and breviary and was notable for his abundant charity to the poor. Soon before his death, he had himself clothed in sackcloth and ashes. Isidore's cult was approved in 1598 and he was declared a Doctor of the Church in 1722.

His reputation is due principally to his writings. Bede, at the time of his death, was working on a translation of extracts from Isidore's book On the Wonders of Nature (De natura rerum), but the Etymologies is his most famous work. This is a kind of encyclopedia which contains elements of grammar, rhetoric, theology, history, mathematics, and medicine, presented in the form of etymologies, which are in fact often erroneous. His Chronica Majora, which covers the years from the Creation to 615, is an influential compilation from various other church historians, but with special information on Spanish history. Other works include biographies of famous men (completing Jerome's work), a summary of Christian doctrine, rules for monks and nuns, and the History of the Goths. From the time of Bede onwards the writings of Isidore figure in medieval library lists almost as frequently as those of Gregory the Great, with whom he shares the unofficial title of ‘Schoolmaster of the Middle Ages’. Feast: 4 April.

Bibliography
Click here for a list of abbreviations used in this bibliography.

• AA.SS. Apr. I (1675), 327–64; P. Séjourné, Le dernier Père de l'Église. Saint Isidore de Séville (1929); E. Bréhaut, An Encyclopaedist of the Dark Ages, Isidore of Seville (1912); M. L. W. Laistner, Thought and Letters in Western Europe (1966); P. Hunter Blair, The World of Bede (1970), pp. 132–7, 291–5; Miscellanea Isidoriana (1936); M. C. Diaz y Diaz (ed.), Isidoriana (1961); works of Isidore in P.L., lxxxi–lxxxiv; crit. edn. of Etymologiae by W. M. Lindsay (1911), of historical works by E. Waitz in M.G.H., Auctores Antiquissimi, xi (1894), 241–506 and of De Natura Rerum by J. Fontaine (1960): Bibl. SS., vii 973–82

The Oxford Dictionary of Saints. Copyright © David Hugh Farmer 1978, 1987, 1992, 1997, 2003, 2004. All rights reserved.