Theodora Anna Doukaina (Greek: Θεοδώρα Άννα Δούκαινα) (1058–1083) was a Byzantine princess, the daughter of emperor Constantine X Dukas and his second wife Eudokia Makrembolitissa. She became the wife of Domenico Selvo, Doge of Venice from 1075 until her death in 1083.
Theodora was married to Domenico Selvo in Constantinople (1075) with full Imperial pageantry, and crowned with the Imperial diadem by her brother, Michael VII Doukas. Teodora brought a large Greek retinue to Venice, and rendered herself extremely unpopular because of her aristocratic bearing and haughty manner. What was then perceived as her Byzantine extravagance included the use of a fork, finger bowls, napkins, and sconce candles. The Dogaressa died of a degenerative illness, which was seen by the Venetians as a divine judgment for her "immoderate" lifestyle. There is an account of her lavish manners written by Peter Damian, the Cardinal Bishop of Ostia, entitled "Of the Venetian Doge's wife, whose body, after her excessive delicacy, entirely rotted away."[1]
It is not possible however for Peter Damian to have written anything about the marriage of Theodora and Domenico: their marriage took place in 1075 and Peter died in 1072. The same stories of Peter Damian have been equally attributed to Maria Argyropoulaina and Giovanni Orseolo: she the niece of the Byzantine Emperors Basil II and Constantine VIII and he the son of Doge Pietro II. Maria and Giovanni were married in Constantinople in 1005 or 1006. Both died in 1007 when a plague swept through the city-state. Peter Damian was born between 995 and 1007: he would have been, at most, 11 years old when Maria, Giovanni and their son arrived in Venice.