Count Boniface, to whom St. Augustin also addressed Letters CLXXXV. and CCXX., was governor of the province of Africa under Placidia, who for twenty-five years ruled the empire in the name of her son Valentinian. By his perfidious rival Aetius, Boniface was persuaded to disobey the order of Placidia, when, under the instigation of Aetius himself, she recalled him from the government of Africa. The necessity of powerful allies in order to maintain his position led him to invite the Vandals to pass from Spain into Africa. They came, under Genseric, and the fertile provinces of Northern Africa fell an easy prey to their invading armies. When the treachery of Aetius was discovered, Placidia received Boniface again into favour, and he devoted all his military talents to the task of expelling the barbarians whom his own invitation had made masters of North Africa. But it was now too late to wrest this Roman province from the Vandals; defeated in a great battle, Boniface was compelled in 430 to retire into Hippo Regius, where he succeeded in resisting the besieging army for fourteen months. It was during this siege, and after it had continued three months, that Augustin died. Reinforced by troops from Constantinople, Boniface fought one more desperate but unsuccessful battle, after which he left Hippo in the hands of Genseric, and returned by order of Placidia to Italy. For fuller particulars of his history, see Gibbon's History of the Decline and Fall of the Roman Empire, ch. xxxiii. ↩