Odoacer had previously become the de facto ruler of Italy following his deposition of Romulus Augustulus, the final emperor of the Western Roman Empire, in 476.

After the collapse of the Hunnic empire in 454, large numbers of Ostrogoths were settled by Emperor Marcian in the Roman province of Pannonia as foederati.

Unlike most other foederati formations, the Goths were not absorbed into the structure and traditions of the Roman military but retained a strong identity and cohesion of their own.

[7] In previous years, a large number of Goths, first under Aspar and then under Theodoric Strabo, had entered service in the Roman army and were a significant political and military power in the court of Constantinople.

Parts of Moesia and Dacia ripensis were ceded to the Goths, and Theodoric was named magister militum praesentalis and consul for 484.

Orestes had reneged on the promise of land in Italy for Odoacer's troops, a pledge made to ensure their neutrality in his attack on Nepos.

After executing Orestes and putting the teenage usurper in internal exile, Odoacer paid nominal allegiance to Nepos (now in Dalmatia) while effectively operating autonomously, having been raised to the rank of patrician by Zeno.

[12] Theodoric with his people set out from Moesia in the autumn of 488, passed through Dalmatia and crossed the Julian Alps into Italy in late August 489.

[13] The Goths now turned to besiege Ravenna, but since they lacked a fleet and the city could be resupplied by sea, the siege could be endured almost indefinitely, despite privations.

[16] But despite this rhetoric, Italy had undergone significant structural changes in the fifth century, which required that Roman administrative traditions had to be adapted by Theodoric's court.

[15] The continuity in administration is illustrated by the fact that several senior ministers of Odoacer, like Liberius and Cassiodorus the Elder, were retained in the new kingdom's top positions.

[18] The close cooperation between Theodoric and the Roman elite began to break down in later years, especially after the healing of the ecclesiastical rift between Rome and Constantinople (see below), as leading senators conspired with the Emperor.

We therefore gladly accede to your request that all the privileges which the foresight of antiquity conferred upon the Jewish customs shall be renewed to you..."[22] and "We cannot order a religion, because no one can be forced to believe against his will.

In 504–505, Theodoric's forces launched a campaign to recover Pannonia and the strategically important town of Sirmium, formerly parts of the praetorian prefecture of Italy, which were now occupied by the Gepids.

Domestically, the Acacian schism between the patriarchates of Rome and Constantinople, caused by imperial support for the Henotikon, as well as Anastasius' Monophysite beliefs, played into Theodoric's hands, since the clergy and the Roman aristocracy of Italy, headed by Pope Symmachus, vigorously opposed them.

[32] The suspicions of Theodoric were confirmed by the interception of compromising letters between leading senators and Constantinople, which led to the imprisonment and execution of Boethius in 524.

The lack of a strong heir caused the network of alliances that surrounded the Ostrogothic state to disintegrate: the Visigothic kingdom regained its autonomy under Amalaric, the relations with the Vandals turned increasingly hostile, and the Franks embarked again on expansion, subduing the Thuringians and the Burgundians and almost evicting the Visigoths from their last holdings in southern Gaul.

To that end, she actively courted the support of the Senate and the newly ascended Emperor Justinian I, even providing him with bases in Sicily during the Vandalic War.

In the event she managed to execute the three leading conspirators, and her position remained relatively secure until, in 533, Athalaric's health began to seriously decline.

[35] Amalasuntha then turned for support to her only relative, her cousin Theodahad, while at the same time sending ambassadors to Justinian and proposing to cede Italy to him.

Justinian indeed sent an able agent of his, Peter of Thessalonica, to carry out the negotiations, but before he had even crossed into Italy, Athalaric had died (on 2 October 534), Amalasuntha had crowned Theodahad as king in an effort to secure his support, and he had deposed and imprisoned her.

[a] This crime served as a perfect pretext for Justinian, fresh from his forces' victory over the Vandals, to invade the Gothic realm in retaliation.

The Gothic War between the Eastern Roman Empire and the Ostrogothic Kingdom was fought from 535 until 554 in Italy, Dalmatia, Sardinia, Sicily and Corsica.

With the fall of Ravenna, the capital of the kingdom was brought to Pavia, which it became the last centres of Ostrogothic resistance that continued the war and opposed Eastern Roman rule.

[37][38] During the second phase (540/541–553), Gothic resistance was reinvigorated under Totila and put down only after a long struggle by Narses, who also repelled the 554 invasion by the Franks and Alamanni.

The war had its roots in the ambition of Justinian to recover the provinces of the former Western Roman Empire, which had been lost to invading barbarian tribes in the previous century (the Migration Period).

As a consequence, the victorious Byzantines found themselves unable to resist the invasion of the Lombards in 568, which resulted in the loss of large parts of the Italian peninsula.

The Basilica of Sant'Apollinare Nuovo, its baptistry, and the Archiepiscopal Chapel follow the typical late Roman architectural and decorative motifs, but the Mausoleum of Theodoric displays purely Gothic elements, such as its construction not from the usual brick, but of massive slabs of Istrian limestone, or the 300-ton single-piece roof stone.

Cassiodorus, hailing from a distinguished background, and himself entrusted with high offices (consul and magister officiorum) represents the Roman ruling class.

Picenum and the northern part of Samnium were areas of heavy Ostrogothic settlement while the same was true of places west of Ravenna near Milan and Pavia along with the beginning of Alps.