The daughter of the Eastern emperor Arcadius, Aelia Pulcheria (AD 398-453) was the granddaughter of Theodosius the Great, the last man to rule the combined Roman Empire.
When her father Arcadius died suddenly in AD 408, Pulcheria was a mere 10 years old. Her brother, Theodosius II, the heir to the throne, was only 8. At the age of 15, Pulcheria became regent for her brother, pledged her virginity to God, and was named Augusta. Perhaps no one had a greater influence on young Theodosius than Pulcheria, as the video excerpt from Sozomen above clearly demonstrates.
Sozomen wrote the brief biography of Pulcheria featured in the above video clip in the mid-440s AD, that is, while Pulcheria was still alive but probably during that period of rivalry with the Eudocia, the wife of Theodosius II, when her power was in eclipse. I posted a variation of this text a while back from a different English translation of Sozomen. Here is a little more from Walford's translation of Sozomen's Ecclesiastical History:
CHAPTER III: THE VIRTUES AND PIETY OF PULCHERIA AND OF HER SISTERS.Pulcheria was influential at the court of the Eastern Roman Empire for nearly 50 years and played a key role during the reigns of two important emperors—Theodosius II and Marcian. She helped them steer a difficult course during a time when the Empire was under assault from every direction as well as internally. Her devotion to orthodox Christianity and particularly her role at the Council of Chalcedon and her veneration of the Blessed Virgin helped set a solid course for Christianity that is clearly perceptible even to this day, more than 1,500 years after her death.
It is said that God on many occasions revealed future events to Pulcheria and conferred on her and on her sisters many special indications of favor. They all pursue the same mode of life. They are sedulous in their attendance in the house of prayer and evince great charity towards strangers and the poor. These sisters generally take their meals and walks together and pass their days and their nights together in singing the praises of God. Like other exemplary women, they employ themselves in weaving and in similar occupations. Although of royal birth and educated in palaces, they avoid idleness as unworthy of the life of virginity to which they have devoted themselves. The favor of God has been, for their sakes, manifested towards their family and the state and the emperor in proportion, as he has grown in years, has increased in power, while all seditions and wars undertaking against him have spontaneously come to nought. [Sozomen, Ecclesiastical History, Book IX, Chapter 3]
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