born April 10, 401, Constantinople
died July 28, 450
Eastern Roman emperor (408–450).
In 402 he was made coemperor with his father, Arcadius (son of Theodosius I ), then became sole ruler of the East at age seven, initially under a regency. A gentle, scholarly man, he allowed relatives and ministers to dominate his government. His generals twice repelled the Persians (422, 447) but failed to evict the Vandal s from Roman Africa (429) and to prevent Attila 's invasions (441–443, 447). The Nestorian heresy caused internal upheaval. Theodosius was credited with building the wall around Constantinople (413), founding the University of Constantinople (425), and promulgating the Theodosian Code (438).