Eudoxia is a fictional character in The Vampire Chronicles by Anne Rice. She appears in the eighth book of the series, Blood and Gold.
After the Fall of Rome, Marius de Romanus, Avicus and Mael move to Constantinople, along with "Those Who Must Be Kept". Shortly after their arrival they are contacted by the young vampires Asphar and Rashid. They ask them to come to Eudoxia, "the vampire empress" in the city.
When her guests arrive she tells them her story. She was around fifteen and about to get married when she was abducted by a vampire. She was then also made one. Her maker she never names, but they stayed together for several years. Eudoxia's maker was very cold and uncaring. After a few years she is taken to "Those Who Must Be Kept" to drink their blood and is directly after left by her maker. She decides to make copies of different texts for mortals in order to know the world. While she's at this she opens her house to mortals and an unnamed young man falls in love with her. He offers to leave his life for her and Eudoxia makes him into a vampire. They spend a few years together until "the Great Fire". The power of all vampires resides in "Those Who Must Be Kept" and one of "the Elders" of their temple has put it to the test. All young vampires are burnt to death as they are in the sun, including Eudoxia's lover. She travels to Egypt and finds out that "Those Who Must Be Kept" are in the custody of Marius. She spends her life trying to find him. She does not succeed and forms a coven in Constantinople. Her companions are Rashid, Asphar and Eudoxia's vampire lover Zenobia. All of them are young when made because Eudoxia thinks they are better off without a connection to their mortal life.
When Marius finally comes to the city, she confronts him. She demands to get possession of "Those Who Must Be Kept", but Marius cannot allow this. He doesn't know if he can trust Eudoxia or what "Those Who Must Be Kept" want. The meeting ends in a fight where Eudoxia is defeated, despite being the elder of the pair, as Marius had drunk more of the blood of Akasha. In the fight Marius discovers that he has "the Fire Gift" when he uses to burn Rashid to ashes. The next night Eudoxia shows up at Marius' house and he agrees to let her see the shrine. As she talks to Akasha and Enkil, Akasha takes her and drinks her blood but Eudoxia is saved by Marius. To heal, Eudoxia needs a victim for feeding. They find a real nobleman, but they let the people know that he has been murdered. The blame falls on Marius and they destroy his house. In his anger he destroys Asphar and all other vampires before he throws Eudoxia to Akasha, where she meets her destruction.