Valentiniānus in Harpers Dictionary of Classical Antiquities
Roman emperor A.D. 426-455, was born 419, and was the son of Constantius III. by Placidia, the sister of Honorius and the
daughter of Theodosius I. He was declared Augustus in 425 by Theodosius II., and was placed over the West, but as he was only
six years of age the government was intrusted to his mother Placidia. During his long reign the Empire was repeatedly exposed to
the invasions of the barbarians; and it was only the military abilities of Aetius which saved the Empire from ruin. In 429 the
Vandals under Genseric crossed over into Africa, which they conquered, and of which they continued in possession till the reign
of Justinian. The weakness of the Empire during this reign was shown also by the fact that the Britons (from whose country the
Roman troops had been withdrawn forty years before), finding it vain to apply to Rome for aid against the incursions of the
Picts, invited the Jutes under Hengest and Horsa to help them, in 449. The Goths likewise established themselves in Gaul; but
Aetius finally made peace with them (439 A.D.), and with their assistance gained a great victory over Attila and the vast army
of the Huns at Châlons in 451. (See Attila.) The power and influence of Aetius excited the jealousy and fears of Valentinian,
who murdered his faithful general in 454. (See Aetius.) In the following year the emperor himself was slain by Petronius
Maximus, whose wife he had violated.
Valentinian III in Roman Biography
Valentinian (Valentinianus) III., (Placidius,)
son of Constantius, born in 419, was made ruler over the
Western empire by his uncle, Theodosius II., (425 A.D.,)
but the government was conducted by his mother, Placidia.
During this period Africa was conquered from
the Romans by Genseric, in consequence of the discord
between the Roman generals Aetius and Honifacius.
Aetius, having previously defeated the Huns under
Attila, was murdered by Valentinian, who was jealous
of his superior ability, (454.) The emperor perished
himself, in 455, by the hand of Petronius Maximus,
whose wife he had dishonoured.
See Gibbon, "Decline and Fall of the Roman Empire ;" Tille-
Histoire des Empereurs."
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Valentinian III in Wikipedia
Flavius Placidius Valentinianus (2 July 419 – 16 March 455), commonly known as Valentinian III, was Western Roman
Emperor from 425 to 455.
Valentinian was born in the western capital of Ravenna in 419. He was the only son of Galla Placidia and Flavius
Constantius. The former was the younger half-sister of the western emperor Honorius, and the latter was at the
time Patrician and the power behind the throne.
Through his mother, Valentinian was a descendent both of Theodosius I, who was his maternal grandfather, and of
Valentinian I, who was the father of his maternal grandmother. It was also through his maternal side that he was
the nephew of Honorius and first cousin to Theodosius II (the son of Honorius' brother Arcadius), who was eastern
emperor throughout most of Valentianian's life. Valentinian had a full sister, Justa Grata Honoria, who was
probably born in 417 or 418 (the history of Paul the Deacon mentions her first when mentioning the children of the
marriage, suggesting she was the eldest). His mother had previously been married to Ataulf of the Visigoths,
and had borne a son, Theodosius, in Barcelona in 414; but the child had died early in the following year, thus
eliminating an opportunity for a Romano-Visigothic line.
When Valentinian was less than two years old, Honorius appointed Constantius co-emperor, a dignity he would hold
until his death seven months later. As a result of all these family ties, Valentinian was the son, grandson,
great-grandson, cousin, and nephew (twice over) of Roman Emperors...