In the seventh century the Spanish church appears intellectually outstanding. It produced a succession of authors of theological, literary, and liturgical texts that were unparalleled, at least in the West, at this time. Many of the writers were also leading figures in the political life of the period, especially the bishops of Seville and Toledo, and most of them were involved in the impressive series of ecclesiastical councils held in Spain during the course of the century. The works of several of them, most notably Isidore of Seville (died 636) and Julian of Toledo (died 690) subsequently circulated widely outside the Iberian peninsula, as would the Hispana collection of canon-law texts, in the compiling of versions of which both these bishops were probably involved. Other authors of the Visigothic period, such as Ildefonsus of Toledo (died 667) and the monastic founder Fructuosus of Braga (died c.670) may have been less well known outside the Iberian peninsula, but within it their writings remained influential for centuries. The largely anonymous liturgical legacy of the Spanish church of the Visigothic period was outstanding for both its literary and theological qualities, and continued in use until finally suppressed in favor of Romano-Frankish traditions in the late eleventh century.
The variety of texts produced in the century and a quarter between the conversion of Reccared and the Arab conquest included works of history, devotional and dogmatic theology, biblical studies, poetry, monastic rules, saints’ lives, polemics, and educational texts, in addition to canon law and liturgy. Many of these items were not original, in that they consisted of rearranged excerpts from the works of earlier writers, thought to be particularly authoritative. But the compiling of them required the existence of libraries containing substantial collections of books. It would be wrong to assume that the often rare and early texts thus used by the authors of the Visigothic period would have been easily available to them, or would have survived in the peninsula from the later Roman period. The evidence for the marked lack of intellectual activity in Spain in the intervening centuries would argue against such a view. What has been called “the Isidoran Renaissance,”from the central role played in it by Isidore of Seville, depended on the presence in Spain by the late sixth century of very specific literary resources. How they came to be there requires an explanation, and it is one that involves looking outside the Iberian peninsula to some contemporary events in Byzantium and Africa.
Around 578/9 a young man from Scallabis (modern Santarém), called John but of Gothic origin, returned home after spending seven years in Constantinople. According to the brief account of him by Isidore of Seville, he had gone there to study. It is noteworthy that despite the ongoing war between the Visigothic kings and the Byzantine forces in Spain, it was clearly possible for a Goth to travel to Constantinople without difficulty, and that Latin literary studies were still being cultivated there.
Isidore’s words are not the only proof that Latin learning was still actively promoted in Byzantium. A Latin poet, Flavius Corippus, who had written a verse panegyric on one of the imperial viceroys of his native province of Africa, was encouraged by his literary success to move to Constantinople in search of patronage. There he wrote another panegyric on the accession of Justin II in 565, which tactfully omitted any hint of opposition to the new emperor’s supposedly unanimous selection by senate, army, and people. Whether this gained him the rewards he sought is not known.
Other Latin authors were also present in Constantinople for rather different reasons. These were bishops from Africa and Italy who were being detained there for opposing the emperor’s theological policies. Several of them wrote works to send to their supporters in the West, urging continued resistance to the emperor’s theology. They also recorded the ill-treatment they had received, which they saw as a modern counterpart to the imperial persecution of the early Christian confessors and martyrs.

Roger Collins. ‘Visigothic Spain 409-711’, Chp. 6: “Books and Readers: The Legacy of Africa”, pp. 147-149. Blackwell Publishing, 2004.