Gaiseric (c. 389 – 25 January 477 AD), also known as Geiseric or Genseric (Latin: Gaisericus, Geisericus; reconstructed Vandalic: *Gaisarīx) was king of the Vandals and Alans from 428 to 477 AD. He ruled over the Vandal kingdom and migrated the kingdom to North Africa, playing a key role in the decline of the Western Roman Empire during the 5th century.
The murder of Roman Emperor Valentinian III, who had betrothed his daughter to Gaiseric's son Huneric, led the Vandal king to invade Italy. The invasion culminated in his most famous exploit, the capture and plundering of Rome in June 455 AD. Gaiseric repulsed two major attempts by both halves of the Roman Empire to reclaim North Africa, inflicting devastating defeats on the forces of Majorian in 460 AD and Basiliscus in 468 AD. As a result, the Romans abandoned their campaign against the Vandals and concluded peace with Gaiseric. Gaiseric died in Carthage in 477 AD and was succeeded by his son, Huneric. During his nearly fifty year rule, Gaiseric transformed a relatively inconsequential Germanic tribe into a major Mediterranean power.
After his father Godigisel's death in a battle against the Franks during the Crossing of the Rhine, Gaiseric became the second most powerful man among the Vandals, only answering to the newly appointed king, his half-brother Gunderic. His status as a noble of the king's family occurred before his more formal accession to the kingship. Jordanes described Gaiseric in the following manner:
Gaiseric ... was a man of moderate height and lame in consequence of a fall from his horse. He was a man of deep thought and few words, holding luxury in disdain, furious in his anger, greedy for gain, shrewd in winning over the barbarians and skilled in sowing the seeds of dissension to arouse enmity.
Gunderic's death in 428 paved the way for Gaiseric's ascension to king of the Vandals; his rise to power was accompanied by continued hostilities against competing powers begun by his brother. He likewise sought ways of increasing the power and wealth of his people (Vandals and some Alans), who then resided in the Roman province of Hispania Baetica in southern Hispania. The Vandals had suffered greatly from attacks from the more numerous Visigothic federates, and not long after taking power, Gaiseric decided to leave Hispania to his rivals. In fact, he seems to have started building a Vandal fleet for a potential exodus even before he became king. Before he could make his move to Africa, Gaiseric was attacked by a large force of Suebi under the command of Heremigarius, who had managed to take Lusitania. However, this Suebic army was later defeated during the Battle of Mérida (428) and its leader drowned in the Guadiana River while trying to flee.
After defending the aforementioned Suebian attack at Mérida, Gaiseric led most of his people—possibly as many as 80,000 persons—to Northern Africa in 428/429; some scholars claim that this figure represents an exaggeration and the number was probably closer to 20,000. Whatever the true numbers, there are indications that the Vandals under Gaiseric may have been invited by the Roman governor Bonifacius, who wished to use the military strength of the Vandals in his struggle against the imperial government under the Roman general, Aetius.
Crossing at the Straits of Gibraltar, Gaiseric led not only his Vandal brethren and army, but was likely accompanied by a contingent of Alans and Goths. Once there, he won many battles over the weak and divided Roman defenders and quickly overran the territory now comprising modern Morocco and northern Algeria. His Vandal army defeated the Bonifatius's army in the battle of Calama and laid siege to the city of Hippo Regius (during which its bishop, Augustine of Hippo, died of an illness), taking it after 14 months of bitter fighting. Gaiseric and his forces then began subduing the interior of Numidia.
A peace between Gaiseric and the Roman Emperor Valentinian III was concluded in 435; in return for recognition of Gaiseric as king of the lands he had conquered, the Vandals would desist from further attacks on Carthage, pay a tribute to the Empire, and send Gaiseric's son Huneric as a hostage to Rome. Gaiseric's treaty with the Romans also included Vandal retention of Mauretania and part of Numidia as foederati (allies under special treaty) of Rome.
Prosper of Aquitaine wrote that Gaiseric had four of his Hispano-Roman counsellors executed after they refused to convert to Arianism. He later banned all non-Arians from serving in his court in the 450s or 460s.
In a surprise move on 19 October 439, Gaiseric captured Carthage, a devastating blow to imperial power, taking advantage of Aetius's preoccupation with affairs in Gaul. Classical scholar Stewart Oost observed, "Thus he undoubtedly achieved what had been his purpose since he first crossed to Africa." Historian Chris Wickham argues that Gaiseric's conquest of Carthage presaged Rome's later collapse. The Romans were caught unaware, and Gaiseric captured a large part of the western Roman navy docked in the port of Carthage. The Catholic bishop of the city, Quodvultdeus, was exiled to Naples, since Gaiseric demanded that all his close advisors follow the Arian form of Christianity. The subsequent sermons of Quodvultdeus paint a "dark picture of the Vandal plunderers."
In the wake of Gaiseric's assault on Carthage, North African bishop and historian, Victor of Vita, wrote in his Historia persecutionis Africanae provinciae sub Geiserico et Hunerico regibus Vandalorum (History of the Persecution in the Province of Africa under the Vandal Kings Gaiseric and Huneric) that the Vandal king immediately began to unrelentingly persecute adherents of the Nicene Christian faith. According to historian Peter Heather, Victor also claimed "that 'innumerable' Nicene bishops and priests were tortured and put to death by Vandals as they sacked and pillaged Nicene churches for their treasures." Heather doubts Victor of Vita's claim of a deliberate and prompt campaign by Gaiseric to persecute Nicene Christians and instead, avows it was more likely not until after 442, when the combined attempt by Eastern and Western Rome to retake Carthage failed; only then did the Vandal king put "considered religious policies into operation." Heather likewise points out how Gaiseric's religious policies seem not to have been applied to the other Vandal provinces of Numidia and Byzacena, where the Nicene Church operated freely in two-thirds of the Vandal kingdom.
Notwithstanding the blow to the imperial coffers caused by Gaiseric's seizure of African revenue and the corresponding grain supply, the Vandal king had no intention of depriving Italy of Africa's grain; he instead wished to sell it to the emperor for profit. Meanwhile, his new status was that of Proconsularis and as such, Gaiseric made Carthage his new residence. Inheriting an already economically efficient and effective state, the tax revenues from his new lands enabled the Vandal conqueror to construct a large fleet that challenged imperial control over the Mediterranean. Gaiseric presided over a mixture of Vandals, Alans, Goths and Romans in Africa, relying on an ad-hoc administration under auspices of the imperial government to legitimize his rule. Latin literary culture even flourished in Carthage.
Gaiseric besieged Panormus (Palermo, Sicily) in 440 AD but was repulsed. Hunnic invasions into the lower Danube forced Constantinople to withdraw forces from Sicily to the benefit of Gaiseric. In a 442 treaty with Rome, the Vandals were recognized as the independent rulers of Byzacena and part of Numidia. In 455, Gaiseric seized the Balearic Islands, Sardinia, Corsica, and Malta, and his fleet soon came to control much of the western Mediterranean. During 455, the Roman emperor Valentinian III was murdered on orders of Petronius Maximus, who usurped the throne. Petronius Maximus also married Valentinian's widow, Licinia Eudoxia, and likewise wedded the imperial couple's daughter Eudocia to his own son; the latter had formerly been promised to Gaiseric's son, Huneric, which contributed a possible casus belli that was exploited by the Vandal king. Gaiseric was of the opinion that these acts voided his 442 peace treaty with Valentinian, and on 31 May, he and his men landed on Italian soil.