Etymologiae (Latin for "The Etymologies"), also known as the Origines ("Origins") and usually abbreviated Orig., is an etymological encyclopedia compiled by Isidore of Seville (c. 560–636) towards the end of his life. Isidore was encouraged to write the book by his friend Braulio, Bishop of Saragossa. The Etymologies summarized and organized a wealth of knowledge from hundreds of classical sources; three of its books are derived largely from Pliny the Elder's Natural History. Isidore acknowledges Pliny, but not his other principal sources, namely Cassiodorus, Servius and Solinus. The work contains whatever Isidore, an influential Christian bishop, thought worth keeping. Its subject matter is extremely diverse, ranging from grammar and rhetoric to the earth and the cosmos, buildings, metals, war, ships, humans, animals, medicine, law, religions and the hierarchies of angels and saints.
Etymologiae covers an encyclopedic range of topics. Etymology, the origins of words, is prominent, but the work covers among other things grammar, rhetoric, mathematics, geometry, music, astronomy, medicine, law, the Roman Catholic Church and heretical sects, pagan philosophers, languages, cities, animals and birds, the physical world, geography, public buildings, roads, metals, rocks, agriculture, ships, clothes, food and tools.
Etymologiae was the most used textbook throughout the Middle Ages. It was so popular that it was read in place of many of the original classical texts that it summarized, so these ceased to be copied and were lost. It was cited by Dante Alighieri, who placed Isidore in his Paradiso, quoted by Geoffrey Chaucer, and mentioned by the poets Boccaccio, Petrarch and John Gower. Among the thousand-odd surviving manuscript copies is the 13th-century Codex Gigas; the earliest surviving manuscript, the Codex Sangallensis, preserves books XI to XX from the 9th century. Etymologiae was printed in at least ten editions between 1472 and 1530, after which its importance faded in the Renaissance. The first scholarly edition was printed in Madrid in 1599; the first modern critical edition was edited by Wallace Lindsay in 1911.
Etymologiae is less well known in modern times, though the Vatican considered naming its author Isidore the patron saint of the Internet. Scholars recognize its importance both for its preservation of classical texts and for the insight it offers into the medieval mindset.
Isidore of Seville was born around 560 in Spain, under the unstable rule of the Visigoths after the collapse of the Roman empire. His older brother, Leander, the abbot of a Seville monastery, supervised Isidore's education, probably in the school attached to his monastery. Leander was a powerful priest, a friend of Pope Gregory, and eventually he became bishop of Seville. Leander also made friends with the Visigothic king's sons, Hermenigild and Reccared. In 586, Reccared became king, and in 587 under Leander's religious direction he became a Catholic, controlling the choice of bishops. Reccared died in 601, not long after appointing Isidore as bishop of Seville. Isidore helped to unify the kingdom through Christianity and education, eradicating the Arian heresy which had been widespread, and led National Councils at Toledo and Seville. Isidore had a close friendship with king Sisebut, who came to the throne in 612, and with another Seville churchman, Braulio, who later became bishop of Saragossa. Isidore was widely read, mainly in Latin with a little Greek and Hebrew. He was familiar with the works of both the church fathers and pagan writers such as Martial, Tertullian and Pliny the Elder, this last the author of the major encyclopaedia then in existence, the Natural History. The classical encyclopedists had already introduced alphabetic ordering of topics, and a literary rather than observational approach to knowledge: Isidore followed those traditions. Isidore became well known in his lifetime as a scholar. He started to put together a collection of his knowledge, the Etymologies, in about 600, and continued to write until about 625.