After the death of Emperor Honorius in 423, primicerius notariorum Joannes was elevated to the throne. Bonifacius refused to acknowledge him, and prevented the plentiful shipments of African grain from reaching Italia. After a revolt in Gaul, and an uprising by general Aëtius, Joannes was overthrown, and Valentinian III, nephew of Honorius, was made Western emperor by the Eastern Roman Emperor, Theodosius II. Bonifacius supported him, and resumed grain shipments. In 427, the magister utriusque militae or commander in chief in defense of Italy, Flavius Felix, sent some troops to quell the outbreak of a revolt of Bonifacius against Valentinian III in northwest Africa, but they were defeated by troops loyal to Bonifacius.
Under the influence of Aëtius, the emperor's mother Galla Placidia convicted Bonifacius of treason against the emperor. Rather than surrender to probable execution, however, Bonifacius called in the support of Vandal mercenaries from their grazing grounds in Hispania. The entire tribe migrated en masse into Africa. However, by the time they arrived, Bonifacius had returned to Placidia's favor, and she had granted him the title of Patricius. He informed the Vandals that their services were no longer needed, but instead of returning to Hispania, they revolted and drove the Roman Empire out of Africa. Bonifacius was defeated near the city of Calama in 431. The Vandals then ruled the diocese until the Eastern Romans under Belisarius recaptured it in 534.
Bonifacius had been recalled to Italy before the Vandals had seized the province, elevated to the rank of magister militum praesentalis and to the dignity of Patricius. Fearing an imminent dismissal, Aëtius and his army of Germanic mercenaries marched against Bonifacius, descending upon Italy; the result was the Battle of Ravenna in 432, which Bonifacius won, despite being mortally wounded. He died several months later, being succeeded by his son-in-law Sebastianus. However, in the following year Aëtius deposed Sebastianus, married Bonifacius's widow Pelagia (with whom he had a child, Gaudentius), and became the de facto ruler of the Western Roman Empire.
- Adrian Goldsworthy, The Fall of the West: The Slow Death of the Roman Superpower, Orion Books Ltd, London. Paperback Edition, 2010, p.328.
- Pétridès, Sophrone. "Calama." The Catholic Encyclopedia. Vol. 3. New York: Robert Appleton Company, 1908. 15 Jul. 2014
- John M. O'Flynn, Generalissimos of the Western Roman Empire
- Stewart I. Oost, Galla Placidia Augusta
|Wikisource has the text of the 1911 Encyclopædia Britannica article Bonifacius.|
|Supreme Commander of the Western Roman Army
| Succeeded by|