- Theodosius II was the son of Arcadius and Eudoxia and was raised to the rank of Caesar at the age of 9 months in January 402.
- When Arcadius died at Constantinople from an illness on 1st May 408, Theodosius II, now only seven years old, succeeded him on the throne.
- The regency was assummed by the Praetorian Prefect, Anthemius. It was Anthemius who made the city of Constantinople almost impregnable by constructing its famous triple wall on the landward side.
- Anthemius restored friendly relations between the Eastern and Western halves of the Roman Empire after the death of Flavius Stilicho in 408.
- In 414 the task of regent was taken over by Theodosius's sister, Aelia Pulcheria
- All the Roman laws from the time of Constantine I onwards were amalgamated into one manuscript, known as the Codex Theodosianus.
- While the western empire was succumbing to the barbarians, the east under Theodosius was relatively prosperous and peaceful.
- Much money was spent paying off the Huns, so that by 450, the treasury was dangerously depleted.
- In 450, Theodosius fell from his horse and broke his back, later dying from his injuries.
- Before he died, he named Marcian, as his successor.