Throughout her life, Placidia was devoted to her religion. Her father Theodosius I was influential in spreading Christianity and attempting to defeat paganism. In 380 Theodosius I issued the Edict of Thessalonica which declared that the “Nicene Trinitarian Christianity to be the only legitimate imperial religion and the only one entitled to call itself Catholic (Wikipedia, 2016). This is one of the many efforts that Theodosius made to convert the Arians to Christianity. Growing up in her father’s household, Placidia learned the benefits of promoting and supporting religion in an empire.
One of the first demonstrations of Placidia’s devotion occurred when she arrived back in Ravenna after being held hostage by the Goths. In 417, Placidia commissioned a church to be built in the northwest section of the city dedicated to the Holy Cross (Salisbury, 2015). Only a small chapel has survived but it gives beautiful examples of mosaics and images of Christ. An architectural achievement of this church is the large dome that rests on the square structure; Placidia hired workers to innovate on a solution. The structure is supported by pendentives, triangular pieces that allow the dome to float above the foundation. This building is known as the Mausoleum of Galla Placidia, however we know that she never meant it as a mausoleum and she is also not buried there (Salisbury, 2015).
Wikipedia. (2016). Mausoleum of Galla Placidia.
Placidia’s most significant involovment in the religious courts was during the unrest over the pope election. On December 27, 418, Pope Zosimus died. While his funeral was taking place, partisans at the Lateran basilica elected Eulalius as the new pope. However, the next day at a different church, priests elected Boniface, who was an advisor to Pope Zosimus’ predecessor (Salisbury, 2015. Two different factions of Roman clergy had elected their own popes thus creating chaos in the city (Wikipedia, 2016).
A letter was sent to the imperial court asking for help by a prefect in Rome named Symmachus. History names Placidia as the one who received this message and turned it to Honorius. Upon hearing that there was two elected popes, Honorius called a meeting with the two parties and some other churchmen on February 8th. However, this council was ineffective and consequently, Honorius instructed both Eulalius and Boniface to stay out of Rome while he summoned another meeting to be held in June at Spoleto (Salisbury, 2015). It is during the preparation for this council that we see Placidia’s influence.
Placidia wrote two letters to invite African bishops to the council, one was addressed to Aurelius of Carthage and the other to seven additional bishops. Placidia writes:
“We would have wished for another cause to see you and to benefit from your august presence. But since unbridled ambition had ushered a battle over the papacy wholly incommensurate with the holy mode of life of such an office, a gathering of bishops, smaller in size than that the number that synodal customs decree, deferred a decision regarding this matter to a larger assembly of the most learned men of whom your sanctity is the foremost. Nor should the rewards of purity and merit be revealed through anyone other than such men, once the faults that the sacred precept of the divine faith are eschewed. Although the letters of the emperor, my blood brother, would have sufficed, I have adjoined my own request for the prompt arrival of your sanctity. I am asking you, holy master and venerable father, that you would grant this double benefit, namely your benediction that we so desire and your much needed opinion, and laying aside all matters deign to exert your effort over confirming the bishop that none would contest.” (Sivan, 2011)
In this letter, we can surmise several things about Placidia. She does not mention that she is the mother of an heir, or that she is the wife of the master general, but only that she is sister to the reigning emperor which grants her every authority. Furthermore, the fact that she is writing the bishops after they have already received an invitation from Honorius suggests that Placidia was very much involved in the religious issues of the day (Salisbury, 2015).
Unfortunately, this council never took place in Spoleto. In March Eulalius entered Rome, in violation of Honorius’ decree, to preside over the Easter ceremonies (Salisbury, 2015; Wikipedia, 2016). Although both Honorius and Placidia favored Eulalius as pope, since he was elected first, this act of disobedience showed that he was unsuitable for the position. The summer council was cancelled and Boniface was recognized as the new legitimate pope on April 3, 419 (Salisbury, 2015). This election crisis demonstrated the power and leadership capability of Placidia in extending her influence over religious leaders as well as her brother.
The final example of Placidia’s devotion to Christianity was during her flight to Constantinople with her children. After the death of her husband Constantius and an argument with Honorius, Placidia traveled across the Adriatic Sea. As they sailed before the shipping season begun, they encountered a terrible storm that threatened their safety. Placidia prayed to John the Evangelist that if he would keep her and her children safe, she would build a church in his honor (Salisbury, 2015).
Years later, when she was safely back in Ravenna, Placidia started construction on the basilica. Though the structure is all that stands from bombings in 1944, we have records of the beautiful mosaic portraits of Placidia’s family. Additionally, above these portraits is the inscription, “To the holy and most blessed apostle John the Evangelist, the Empress Galla Placidia with her son the Emperor Placidus Valentinian and her daughter the Empress Justa Grata Honoria fulfill the vow of liberation from the dangers of the sea” (Salisbury, 2015). The church is now known as the San Giovanni Evangelista (Wikipedia, 2016). Placidia led her life with the principle of “buildings for blessings”. Since she was blessed with riches and wealth, Placidia generously supported the Catholic Church by building many churches over her lifetime. 
Wikipedia. (2016). San Giovanni Evangelista
Before she died in 450, Placidia wrote a letter that describes how she thought of her life. She addressed the letter from “Galla Placidia, most pious and prosperous, perpetual Augusta and mother” (Salisbury, 2015). By noting her peity to God before her imperial rank demonstrates the importance of religion and church in the empress’ life. Learning from her father, Placidia led a life of religious devotion that was demonstrated in her church building, constant prayers, and pursuit of a holy life.
References
Salisbury, J. (2015). Rome’s Christian empress: Galla Placidia rules at the twilight of the empire. Baltimore: John Hopkins University Press.
Sivan, H. (2011). Galla Placidia: The Last Roman Empress. New York, New York: Oxford University Press.
Wikipedia. (2016). Galla Placidia. Wikipedia. Retrieved December 15, 2016 from https://en.wikipedia.org/wiki/Galla_Placidia
Wikipedia. (2016). Theodosius I. Wikipedia. Retrieved December 15, 2016 from https://en.wikipedia.org/wiki/Theodosius_I
Legio I Lynx Fulminata 