which year marks the beginning of this western empire?
395 A.D.
Western Roman Empire
The Western Roman Empire comprises the western provinces of the Roman Empire at any time during which they were administered by a separate independent Imperial court; in particular, this term is used in historiography to describe the period from 395 to 476
what became of the eastern roman empire after the collapse of the western roman empire It survived the fragmentation and fall of the Western Roman Empire, continued to exist for an additional thousand years until it fell to the Ottoman Empire in 1453.
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Western Roman Empire [SEP] Introduction
The Western Roman Empire comprises the western provinces of the Roman Empire at any time during which they were administered by a separate independent Imperial court; in particular, this term is used in historiography to describe the period from 395 to 476, where there were separate coequal courts dividing the governance of the empire in the Western 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 separate empires but viewed it as a single polity governed by two separate imperial courts as an administrative expediency.