The Gothic War between the Byzantine Empire during the reign of Emperor Justinian I and the Ostrogothic Kingdom of Italy took place from 535 to 554 in the Italian Peninsula, Dalmatia, Sardinia, Sicily and Corsica. It was one of the last of the many Gothic Wars against the Roman Empire. The war had its roots in the ambition of the Byzantine emperor Justinian I to recover the provinces of the former Western Roman Empire, which the Romans had lost to invading barbarian tribes in the previous century, during the Migration Period.

The term Western Roman Empire is used in modern historiography to refer to the western provinces of the Roman Empire, collectively, during any period in which they were administered separately from the eastern provinces by a separate, independent imperial court. Particularly during the period from AD 395 to 476, there were separate, coequal courts dividing the governance of the empire into the Western provinces and the Eastern provinces with a distinct imperial succession in the separate courts. The terms Western Roman Empire and Eastern Roman Empire were coined in modern times to describe political entities that were de facto independent; contemporary Romans did not consider the Empire to have been split into two empires but viewed it as a single polity governed by two imperial courts for administrative expediency. The Western Empire collapsed in 476, and the Western imperial court in Ravenna disappeared by AD 554, at the end of Justinian's Gothic War.