Who were the Vandals and where did they came from ?
Vandals belong to the group of Eastern Germanic tribes. The main Vandal tribal groups were the Hasdingi and the Silingi. It is thought that at first they inhabited the Scandinavian Peninsula and Jutland, from where they displaced to the banks of the Oder river. In the second half of the II century, they began to move south. They participated in the Marcomannic Wars and in 147 C.E. the Roman Emperor Marcus Aurelius gifted them land for settlement in Dacia. They stayed there until the first half of the IV century when, under pressure from the Goths, and with the permission Emperor Constantine I the Great, in 335 C.E., they settled as Roman Federates in Pannonia. During that time they  accepted Christianity in the form of Arianism, and gradually formed among them a state organization in the form of a kingship. At the beginning of the V century, under pressure from the Huns, King Godigisel led his people from the rich Pannonia westward along the Danube river.
The journey to north Africa
During the journey the Vandals were joined by the Suebi (confederation of North Germanic peoples) and the Alans, which in 402 C.E. devastated Raetia, and in 405 C.E. together crossed the Neckar river. They were led by Gunderic, son of the late Godigisel and at the end of 406 C.E., the Vandals, with the help of Alans and Suebi, broke the Roman line of defense at Mainz on the Rhine and crossed the frozen river entering Gaul. Their stay in Gaul had been short. Crossing Gaul in the fall of 409 C.E. they entered the Iberian Peninsula, where, after two years, they concluded an agreement with representatives of the Roman government for a settlement in the territories of the Empire. One part of the Vandals, particularly the Hasdingi along with the Suebi, settled in the northwestern part of the peninsula, in Galicia and the other part consisting of the Silingi settled in Baetica, while the Alans settled in the southwestern and southeastern parts of the peninsula, in Lusitania and the province of New Carthage. In 416 C.E. persuaded by the Romans, Visigoths from Gaul entered Spain and attacked the Vandals, Alans and Suebi. Despite successful warfare, Visigoths still failed to achieve a decisive victory and after two years (418 C.E.)  they returned to Gaul. However the war with the Roman Empire continued on with variable success. After the Alan defeat from the Visigoths in 426 C.E., the Alans offered  the crown to Gunderic, and he had started calling himself king of the Vandals and Alans. Under pressure from the permanent struggles with the Romans and their allies the Visigoths, and attracted by the rich granaries of the Roman province of North Africa, the Vandals decided to leave Spain behind. Under the leadership of king Genseric (428-477 C.E.), son of Godisel and half brother to Gunderic along with the Alans in the year 429 C.E. they crossed Gibraltar and moved to North Africa. It is thought that at this time the Vandals along with the Alans, numbered approximately 80,000 people, of which about 20,000 were military capable men. To their advantage were the intrigues of the Roman courtyard during the reign of the minor Valentinian III (425-455 C.E.), and the situation in North Africa. Namely, over the 427-428 C.E., the local Berber tribes had rejected the authority of the Romans, and an additional destabilizing factor were the followers of bishop Donatus, who rejected the primacy of the Roman Church in this region.
The Vandals under the rule of King Genseric (428-477 C.E.)
Using this situation, Genseric, marching almost two thousand kilometers (1242 miles), managed to conquer most of the territories of the Roman province. The Vandals occupied territories of present day Morocco and Algeria who gravitate to the Mediterranean Sea and the west of Tunisia, and later conquered the east of Tunisia and Tripoli. After a Roman military action, in 435 C.E., the two sides signed a peace agreement, under which the Vandals and Alans are recognized as federates of the Empire. But Genseric was not permanently satisfied with the outcome. Under his leadership the Vandals in  439 C.E. captured the capital of the Roman province of Africa-Carthage. In this region of North Africa in 439 C.E. a new barbarian state was formed  on the territory of the Roman Empire – Vandal or rather Vandal-Alan Kingdom, with its capital being Carthage. To regain their power in North Africa, the Romans in 441 C.E took from Italy, a major military expedition against the Vandals and Alans. However, the expedition did not give the expected results, on the contrary. Having built a fleet Genseric in 442  C.E. conquered Sicily, and quickly after a peace treaty was signed with Rome. Under the peace agreement, the Romans formally recognized the conquerors sovereignty of territories in North Africa all the way to Tripolitania. Thus, in fact, the Roman Empire formally recognized the new barbaric state on its territory. After the conquest of North Africa, the Vandals committed mass confiscation of the property of the Roman aristocracy, and for an easier management the  entire kingdom was divided into five provinces. At the same time it took place a process of robbing the Church estates. Namely because they were Arian, the conquerers committed appropriation of the wealth of the Roman Church. In fact, expropriation of property was carried out on all the conquered territories, but only in areas where Vandals had settled (modern Tunisia and Tripolitania).
The Sack of Rome
Vandals and Alans from North Africa took new conquest expeditions and significantly expanded the borders of their country. Among others, they conquered the Balearic Islands, Sardinia and Corsica, with that by the middle of the V century, they became a major maritime power in the western Mediterranean. On the call from the deposed Roman royal family with which one of Genseric’s son’s was promised marital ties, the Vandals on June 2 455 C.E. conquered and plundered Rome. They destroyed  many cultural (art) monuments. This event represented the base of the term “vandalism’, which appeared later, denoting merciless, savage destruction of cultural values. So the Vandals had the”honor ” to give their name to this destructive term, although their devastations were no bigger or worse than devastations of many other peoples and tribes taken in different historical eras (like those of the Huns, Goths, Avars and other peoples). Genseric’s Fleet in 468 C.E. managed to defeat the Byzantines and even tried to invade the Peloponnese. However, in 476 C.E lasting peace was concluded  with the Eastern Roman Empire .
The crumbling and fall of the Vandal Kingdom
After the death of Genseric, according to the law which he made during his lifetime, the title of King should be inherited by the eldest male member of the ruling house.  Genseric was succeeded by his son Huneric (477-484 C.E). This ruler, initially tolerant towards Catholics, was carried  with the idea that all the Catholic bishops in his kingdom (460) to accept Arianism. Although he made such a decision and the council convened in 484 C.E. he had failed to carry out such a prospect. His successor Gunthamund (484-496 C.E.) implemented the policy of religious tolerance, whereby the Catholic bishops were even returned parts of previously confiscated properties. But in the time of King Trasamund (496-523 C.E.) ended many years of persecution of the Catholic Church, which had begun under his uncle Huneric, a move which improved the Vandals’ relations with the Byzantine Empire. Procopius states that he was “a very special friend of the Emperor Anastasius. Тhe new ruler Hilderic (523-530 C.E.), son of Huneric was the most tolerant Vandal king to Catholics, which was understandable, since he was the nephew of the Roman Emperor Valentinian III. This religious policy cost him his life because the Arian priests organized  a conspiracy in which Hilderic was liquidated. Under the pretext of restoring the legitimate ruler on the Vandal throne, the Byzantine army led by the renowned military commander Belisarius in 533 C.E. landed in North Africa and in December of the same year  finally defeated the army of the last Vandal King Gelimer (530-534), grandson of Genseric, in Carthage. He surrendered to the Byzantines the next year 534 C.E and the Vandal Kingdom was  annexed by the Byzantine Empire. Part of the Vandals were sold as slaves or taken into the service of the Eastern Roman Empire and taken to the eastern front to fight against the Persians, while the rest were assimilated by the local population. The Vandal-Alan state was the first of barbarian states created on the territory of the Western Roman Empire, which became the victim of the ambitious plans of the Byzantine emperor Justinian I to restore the former power of the Roman state or with other words recovery of Roman power over other territories, which at the time of Constantine I the Great entered the composition of the Roman Empire