Niece of the patriarch Michael I Keroularios, Eudokia served as regent for seven months after the death of her husband Constantine X. In 1068 she married Romanos Diogenes, a member of the military aristocracy. It was hoped that under his leadership the empire would be able to resist the mounting pressure exerted by its enemies. After the defeat of Romanos at Mantzikert in 1071 and his subsequent release, Eudokia hesitated to accept him back as emperor. The decision was taken out of her hands by her brother-in-law John Doukas. John had Michael VII (Eudokia’s son by Constantine X) named autokrator, and made it known that Romanos’s claim was not to be recognized. Eudokia was shortly after confined to a monastery at Piperoudion.
There are a number of seals that depict Eudokia. The seal shown above is hers alone and shows the empress standing, wearing a crown and a loros, and holding a cross scepter. The obverse shows the Mother of God orans. On seals from her brief regency, Eudokia is the central figure, flanked by her sons Michael VII and Constantine. Eudokia also appears on the seals issued during the reign of Romanos IV Diogenes, but these will be discussed in the next section. For the seals of Eudokia's family see the Doukas Dynasty in the Dynasties of Empire section.