Eutropia was born after her parents married in late 289. Eutropia's father was ConstantiusI, who was made an emperor in 293. Eutropia's mother was Theodora. Theodora was the daughter of the emperor Maximian and his wife, who also had the name Eutropia. Eutropia had an older half-brother, Constantine the Great, and five other full siblings, the other children of Constantius and Theodora.