St. Evdokia of Persia was born in Anatolia–modern-day Turkey–in the fourth century. She was one of the largely anonymous Martyrs of Persia, and can sometimes be confused with St. Evdokia of Heliopolis or the empress Saint Evdokia, who was married to Byzantine Emperor Theodosius II.
The Martyrs of Persia under Shapur II were Assyrian Christian martyrs who were put to death by Shapur II of Persia, who reigned from 309–379, for failing to renounce their faith. This was a sharp departure from the early history of Christianity in Persia, which was widely tolerated. But when Byzantine emperor Constantine the Great converted to Christianity and made it the official religion of his empire, Shapur II came to view the Christian presence in his realm as hostile and potentially threatening. His suspicions hardened after Roman armies defeated his forces in war. As a result, he ordered that all Christian churches be destroyed, their clergy executed, and--later--all professed Christians be put to death. Calculations of the number of Persian Christians executed by his edicts vary, though estimates suggest many thousands.
The Persian army brought St. Evdokia into captivity along with some 9,000 other Christians. While captive, she took it upon herself to educate her fellow prisoners in Holy Scripture since she knew them well. She also preached to and converted many of the Persian women with whom she came into contact to life in Christ–which led to what may have been a more severe martyrdom than she might otherwise have suffered.
Troparion
Your lamb Eudokia calls out to You, O Jesus, in a loud voice: "I love You, my Bridegroom, and in seeking You, I endure suffering. In baptism, I was crucified so that I might reign in You, and I died so that I might live with You. Accept me as a pure sacrifice, for I have offered myself in love." Through her prayers, save our souls, since You are merciful.
Holy mother Evdokia, pray to God for us!
Sources: oca.org, britannica.com, wikipedia.org.