<P> The Western Roman Empire existed intermittently in several periods between the 3rd and 5th centuries, after Diocletian's Tetrarchy and the reunifications associated with Constantine the Great and Julian the Apostate (331 / 2--363). Theodosius I divided the Empire upon his death (in 395) between his two sons . Finally, eighty - five years later, Zeno of the Eastern Empire recognized the reality of the Western Empire's reduced domain--Roman power ceased to exist even in the Italian Peninsula--after the deposition of Romulus Augustus and the subsequent death of Julius Nepos, and therefore proclaimed himself the sole emperor of the Roman Empire . </P> <P> The rise of Odoacer of the Foederati to rule over Italy in 476 was popularized by eighteenth - century historian Edward Gibbon as a demarcating event for the end of the Western Empire and is sometimes used to mark the transition from Antiquity to the Middle Ages . Imperial rule was reimposed in large parts of the West in the sixth century by the armies of the Eastern Roman Empire but political upheaval in the East Roman heartlands saw the Western provinces slip away once more, this time for good . Frankish king Charlemagne would be declared in AD 800 in an attempt to revive the Western Roman Empire; this new imperial line would evolve in time into the Holy Roman Empire, which revived the imperial title but was otherwise in no meaningful sense an extension of Roman traditions or institutions . </P> <P> As the Roman Republic expanded, it reached a point where the central government in Rome could not effectively rule the distant provinces . Communications and transportation were especially problematic given the vast extent of the Empire . News of invasion, revolt, natural disasters, or epidemic outbreak was carried by ship or mounted postal service, often requiring much time to reach Rome and for Rome's orders to be realized in the province of origin . For this reason, provincial governors had de facto rule in the name of the Roman Republic . </P> <P> Prior to the establishment of the Empire, the territories of the Roman Republic had been divided in 43 BC among the members of the Second Triumvirate: Mark Antony, Octavian and Marcus Aemilius Lepidus . Antony received the provinces in the East: Achaea, Macedonia and Epirus (roughly modern Greece, Albania and the coast of Croatia), Bithynia, Pontus and Asia (roughly modern Turkey), Syria, Cyprus, and Cyrenaica . These lands had previously been conquered by Alexander the Great; thus, much of the aristocracy was of Greek origin . The whole region, especially the major cities, had been largely assimilated into Greek culture, Greek often serving as the lingua franca . </P>

Why did roman empire split into east and west