can you name a few regions that were a part of this empire?
Mediolanum and Ravenna
Western Roman Empire
 On the death of Theodosius I in 395, he divided the empire between his two sons, with Honorius as his successor in the West, governing briefly from Mediolanum and then from Ravenna, and Arcadius as his successor in the East, governing from Constantinople.
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. which year marks the beginning of this western empire? 395 A.D.
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Western Roman Empire [SEP] Introduction
Though the tetrarchic system would collapse in a matter of years, the East–West administrative division would endure in one form or another over the coming centuries. As such, the Western Roman Empire would exist intermittently in several periods between the 3rd and 5th centuries. Some emperors, such as Constantine I and Theodosius I, governed as the sole "Augustus" across the Roman Empire. On the death of Theodosius I in 395, he divided the empire between his two sons, with Honorius as his successor in the West, governing briefly from Mediolanum and then from Ravenna, and Arcadius as his successor in the East, governing from Constantinople.