[3] Mommsen also claimed that she had a daughter also named Flavia Domitilla[4] who married Titus Flavius Onesimus[Note 1] but later retracted this theory.

"[2] Cassius Dio (c. 155–235) reports in his Roman History: "Domitian slew, along with many others, Flavius Clemens the consul, although he was a cousin and married to Flavia Domitilla, who was also a relative of the emperor's.

In his Church History, written at the end of 323 or 324, Eusebius, speaking of "writers who were far from our religion", says that "they recorded that in the fifteenth year of Domitian Flavia Domitilla, daughter of a sister of Flavius Clement, who at that time was one of the consuls of Rome, was exiled with many others to the island of Pontia in consequence of testimony borne to Christ.

[16] Writing of the death in 404 of Saint Paula, Jerome says that on her way to the Holy Land, "the vessel touched at the island of Pontia ennobled long since as the place of exile of the illustrious lady Flavia Domitilla who under the Emperor Domitian was banished because she confessed herself a Christian; and Paula, when she saw the cells in which this lady passed the period of her long martyrdom, taking to herself the wings of faith, more than ever desired to see Jerusalem and the holy places".

The Domitilla of Cassius Dio was the wife of Flavius Clemens and was exiled to the island of Pandateria in the context of persons who "drifted into Jewish ways".

[21][22][23] Furthermore, it presents Domitilla, not as a wife and mother of seven children but as a formally consecrated Christian virgin, a description absent also from the writings of Eusebius and Jerome.

Until the Roman Martyrology was completely revised in 2001, it had the following entry under 7 May: "At Terracina, in Campania, the birthday of blessed Flavia Domitilla, virgin and martyr, niece of the Consul Flavius Clemens.

She received the religious veil at the hands of St Clement, and in the persecution of Domitian was exiled with many others to the island of Pontia, where she endured a long martyrdom for Christ.

Based closely on the Acts of Saints Nereus and Achilleus, it said under the date of 12 May: "The Roman virgin Flavia Domitilla, niece of Emperors Titus and Domitian, after receiving the religious veil of virginity at the hands of blessed Pope Clement, was accused by her fiancé Aurelianus, son of Consul Titus Aurelius, of being a Christian and was banished by Emperor Domitian to the island of Pontia, where she underwent a long martyrdom in prison.

She was always shown to be more and more constant and, under the Emperor Trajan, fire was set, by order of the judge, to her room and, together with her foster sisters Theodora and Euphrosyna, she consummated her glorious martyrdom on 7 May.

On this day [12 May] the bodies of the two brothers [Nereus and Achilleus] and Domitilla were brought back from the cardinal-deaconry of Saint Adrian to the basilica of these martyrs, the Titulus Fasciolae.

"[41] The Roman Martyrology now states under 7 May: "At Rome, commemoration of Saint Domitilla, martyr, daughter of the sister of Consul Flavius Clemens, who, being accused during the persecution of Emperor Domitian of denying the pagan gods, was because of her witness to Christ banished with others to the island of Pontia and there underwent a long martyrdom.