Ferguson 15 notes

The accompanying displacements and interchanges of population had a profound effect on Christianity in the western regions. (286)

Medieval civilization was built up from the culture of the later Roman Empire (especially Roman literature, law, and governmental institutions), the customs of Germanic peoples, and the church with its faith and practices (specifically the theology of Augustine and the pre-eminence of the papacy). (286)

It was of great significance that when the barbarian Germans swept through the western Roman world in the fifth century, they came (for the most part) not as pagans but as Arian Christians. The first of the Germanic peoples to be reached with the Christian gospel were the Goths. One of their bishops, Theophilus, was at Nicaea. (289)

Church History, Volume 1: From Christ to Pre-Reformation F. The Ostrogoths (East Goths) and Italy

Boethius represents a transition from the Fathers to the Scholastics, for his approach anticipated the work of the later Schoolmen.

Church History, Volume 1: From Christ to Pre-Reformation F. The Ostrogoths (East Goths) and Italy

Dionysius has a wider cultural significance because he introduced a system of dating based on the Christian era, beginning with the incarnation (AD for anno domini, “in the year of the Lord”) instead of the secular method according to the consuls of Rome and the empire of Diocletian.

Church History, Volume 1: From Christ to Pre-Reformation A. The Christian Literary Response to the Invasions

Orosius promoted the view that both the Hebrew and Roman peoples had a part to play in the salvation of the world.

Church History, Volume 1: From Christ to Pre-Reformation VI. The Later Stages of the Augustinian-Pelagian Controversy

As we saw in chapter 14, the first phase of the Pelagian controversy was Augustine versus Pelagius, and the second phase was the Semi-pelagian reaction against Augustinianism in southern Gaul. A third phase opened with the defense of Augustine by his supporters in Gaul.

Church History, Volume 1: From Christ to Pre-Reformation VI. The Later Stages of the Augustinian-Pelagian Controversy

A fourth phase in the controversy saw renewed opposition to strict Augustinianism as expressed by Lucidus, whose views on predestination were condemned in a synod at Arles in 473.

Church History, Volume 1: From Christ to Pre-Reformation VI. The Later Stages of the Augustinian-Pelagian Controversy

Although Caesarius had been trained at the monastery at Lerins, he adopted a moderate Augustinianism that incorporated Augustine’s emphasis on the priority of grace, accepted the monastic emphasis on good works and their reward at the judgment, and passed over the more controversial aspects of Augustine’s teaching on predestination and perseverance.

Church History, Volume 1: From Christ to Pre-Reformation VI. The Later Stages of the Augustinian-Pelagian Controversy

Although there continued to be adherents of a strict Augustinianism, the general view in the Latin West was that of Pope Gregory the Great (chapter 16), who accepted prevenient grace without its irresistible or particularistic aspects.

Church History, Volume 1: From Christ to Pre-Reformation A. Fourth and Fifth Centuries before Leo the Great

By far the most important bishop of Rome for advancing the claims of his see in the fourth century was Damasus (366–84), who came to the office after a contested election in which there was bloodshed between his supporters and those of his rival Ursinus. Damasus made frequent reference to Rome as “the apostolic see” and spoke of the “primacy of the Roman see” on the basis of Matthew 16:18.

Church History, Volume 1: From Christ to Pre-Reformation B. Leo the Great and Gelasius

Augustine provided the intellectual substance for the medieval Western church, and Leo outlined its institutional form.