Bede's Ecclesiastical History of England, ed. by A.M. Sellar, , at sacred-texts.com
In the year of our Lord 423, Theodosius, the younger, the forty-fifth from Augustus, succeeded Honorius and governed the Roman empire twenty-six years. In the eighth year of his reign, Palladius was sent by Celestinus, the Roman pontiff, to the Scots that believed in Christ, to be their first bishop. In the twenty-third year of his reign, Aetius, a man of note and a patrician, discharged his third consulship with Symmachus for his colleague. To him the wretched remnant
of the Britons sent a letter, which began thus :—"To Aetius, thrice Consul, the groans of the Britons." And in the sequel of the letter they thus unfolded their woes:—" The barbarians drive us to the sea; the sea drives us back to the barbarians: between them we are exposed to two sorts of death; we are either slaughtered or drowned." Yet, for all this, they could not obtain any help from him, as he was then engaged in most serious wars with Bledla and Attila, kings of
the Huns. And though the year before this Bledla had been murdered by the treachery of his own brother Attila, yet Attila himself remained so intolerable an enemy to the Republic, that he ravaged almost all Europe, attacking and destroying cities and castles. At the same time there was a famine at Constantinople, and soon after a plague followed; moreover, a great part of the wall of that city, with fifty-seven towers, fell to the ground. Many cities also went to ruin, and the famine
and pestilential state of the air destroyed thousands of men and cattle.