The last emperor to rule the entire Roman Empire before its was permanently split between the West and East, Theodosius was born in modern-day Spain ca. AD 346. He was chosen by Gratian to assume command of the army after the death of Emperor Valens at the hands of the Goths during the Battle of Adrianople. Theodosius I was elevated to Eastern Emperor in 379, and assumed control of the West as well after the death of Valentinian II in 392. The final three years of his reign were the last time a single Emperor would rule the entirety of the Roman Empire.