Excepting only Augustine, Isidore of Seville was certainly the most influential, and the most prolific, Latin writer of late Antiquity. The voluminous oeuvre of the Spanish polymath would still have represented a challenge for the most intellectually voracious seventh-century audience, and his contemporaries would surely have agreed. As the later bibliography compiled by Isidore's correspondent, Braulio of Saragossa, vividly demonstrates, the Sevillan bishop was extraordinarily prolific over the course of his eighty-year life. In this posthumous list, Isidore is accredited with an accomplished work of natural history, three different grammatical commentaries, five exegetical pieces of varying kinds, two pastoral rules, at least three different historical compositions and, as if to round off a startlingly productive literary career, perhaps the single most influential book of the Latin Middle Ages – the Etymologiae or Origines in twenty books. The last of these works represented the first attempt to provide an original summation of human knowledge for five and a half centuries and provided the yardstick against which all medieval encyclopaedias – and many later compositions – would be judged.

Isidore's productivity is all the more remarkable within the context of the world in which he lived. While Visigothic Spain was less moribund than contemporary Gaul in literary terms, and witnessed the production of a number of historical, hagiographical and theological compositions alongside the works of Isidore, the bishop of Seville remains the single outstanding figure of the period.