It is the great flowering of the imperial Church: John Chrysostom (d. 407) begins the century as Patriarch of Constantinople, Augustine writes his classic works, Jerome translates the Greek and Hebrew Scriptures into the Latin Vulgate, the Council of Ephesus (431) declares Mary to be Theotokos while the Council of Chalcedon (451) defines the two natures of Christ. Pope Leo the Great defines doctrine and turns away the Huns from Rome by sheer force of personality. (He is also the first Bishop of Rome to exercise civil authority and probably the first to enforce discipline over other bishops, so many people call him the first real pope.)
It is the time of the Germanic invasions of the empire: the Visigoths sack Rome in 410, the Vandals in 455. The Visigoths, Burgundians, and Franks help Aetius (391-454) defend the empire against Attila and his Huns at the Battle of Chalons (451). The Suebians take over Gallicia. The Vandals set up a kingdom in Carthage. The Britons invite the Angles, Saxons, and Jutes over to defend them against the Picts and Scoti (Irish) in the 440s, and the oversea tribes decide to stay and establish kingdoms of their own: the origin of the English. (The Anglo-Saxons were particularly disposed to this adventure since the Danes had begun expanding out of Scania and subjugating the Ingvaeonic Heathobards and Jutes to their west.) The second half of the century is thus the age of King Arthur (if he existed), with the Battle of Mount Badon coming c. 490. After the dismissal of the last western emperor in 476, Germanic warrior-kings – first Odoacer, then Theodoric the Ostrogoth – rule Italy, the first barbarians to do so in their own names. (Theodoric will be remembered in German legend and fantasy as Dietrich von Bern.) Clovis I becomes King of the (Salian) Franks in 481 and begins the transformation of northern Gaul into Frankia.
In Ireland, the century opens with Niall of the Nine Hostages growing up. He will become the first High King of Ireland and found the Ui Neill dominance of northern Ireland that will last for centuries. On one of his piratical raids to the shores of Britain, his men take a captive who is sold into slavery. After six years, the slave escapes, finds his calling, and returns to convert his captors. He is known to us as St. Patrick.
Patrick’s style of monasticism, which took hold of the Irish imagination, was largely derived from earlier, eastern monasticism. It was a drastic sort of self-surrender. Since the age of persecutions had passed, those wishing to demonstrate their trust in God resorted to astounding austerities. They called it “the white martyrdom.” But toward the end of the century, Benedict of Nursia (born c. 480) leaves his studies and becomes a monk (c. 500). He will define a new kind of monasticism in the next century, when he founds the community at Monte Cassino and writes his famous Rule. The new monasticism will be, above all else, orderly; people will become monks and nuns not to lose themselves, but to find themselves.
The Arian controversy raged throughout the 5th Century. Orthodoxy had triumphed in the imperial Church, but the Goths and other Germanic tribes tended to be Arian, thus making the religious dispute an ethnic marker. But with the conversion of Clovis from paganism direct to Catholic Christianity in 496, the phenomenon of new Germanic tribes embracing Arianism came to an end. The issues and passions of the classical world started to give way to the particular problems to be addressed by early medieval society.
Augustine, Attila, Arthur, Dietrich, Niall, Patrick, Benedict. This is the century of transition between one era and another. It is the source of many legends and saints’ lives. And it is not simply because of the wreck of civilization that we know so little about it; records exist and sequences can be puzzled out. But our schooling skips over this entire fascinating age with a couple of quick statements. People presume nothing of importance happened. They’re wrong.