Complex sentence: Some inhabitants evacuated from the abandoned province were settled on the south side of the Danube and their new homeland renamed Dacia accordingly, in order to diminish the impact that abandoning the original Dacia had on the Empire's prestige.
Split into simpler sentences: Some inhabitants evacuated from the abandoned province settled on the south side of the Danube. They renamed their new homeland Dacia to diminish the impact that abandoning the original Dacia had on the Empire's prestige.