The 5th-century date CDIII refers to the year 403 CE, which was the third year of the fifth century in the Common Era. This was a time of great change and upheaval in the Roman Empire, as it was transitioning from the Late Roman period to the Early Middle Ages. The Visigoths had sacked Rome in 410 CE, and the Western Roman Empire had officially ended in 476 CE. During this time, the Eastern Roman Empire, or Byzantine Empire, was beginning to take shape.