Flavia Domitilla was a Roman matron of the imperial family at the end of the first century. Her mother was a sister of the emperors Titus and Domitian. She married Titus Flavius Clemens, a cousin of the emperors, and Domitian adopted their two young sons as his heirs.

Clemens, who had been consul, was tried on very slight grounds. The historian Dio Cassius says husband and wife were charged with 'atheism' and Jewish practices, which the Catholic Encyclopedia reads as meaning they were Christians. Clemens was put to death and Domitilla was banished to the island of Pandataria.

Her faith is beyond doubt: De Rossi showed that the Christian Catacomb of Domitilla lay on land belonging to her. Some ancient writers make her the consul's niece and place her exile on Pontia, which led to the idea of two Domitillas; the Catholic Encyclopedia notes this is disputed.

Flavius Clemens was cousin germa^n of the emperor^ and was certainly consul in 95. He had two sons, whom the emperor had resolved should succeed him on the throne, and he had changed their names to Vespasian and Domitian. But Flavius Clemens was executed, and his wife, DomitiUa, was banished to Pontia, whilst — so the two accounts are reconciled — his niece Flavia DomitiUa was sent to Pandateria.

A Christian Roman matron of the imperial family who lived towards the close of the first century. She was the third of three persons (mother, daughter, and grand-daughter) who bore the same name. The first of these was the wife of the Emperor Vespasian; the second was his daughter and sister to the Emperors Titus and Domitian [Roman emperor 81–96]; her daughter, the third Domitilla, married her mother's first cousin to Titus Flavius Clemens, a nephew of the Emperor Vespasian and first cousin to Titan and Domitian. From this union there were born two sons, who, while children, were adopted as his successors by Domitian and commanded to assume the names Vespasianus and Domitianus. It is quite probable that these two lads had been brought up as Christians by their pious mother, and the possibility thus presents itself that two Christian boys at the end of the first century were designated for the imperial purple in Rome. Their later fate is not known, as the Flavian line ended with Domitian. Clement, their father, was the emperor's colleague in the consular dignity, but had no sooner laid down his office than he was tried on charges of the most trivial character (ex tenuissimâ suspicione — Suetonius, Vita Domit.). Dio Cassius (lxvii, 14) says that husband and wife alike were guilty of atheism and practice of Jewish rites and customs. Such accusations, as is clear from the works of the Christian apologists, could have meant nothing else than that both had become Christians. Though doubts have been expressed, because of the silence of Christian tradition on the subject, as to whether Clement was a Christian, the affirmative view is considerably strengthened by the further accusation of Suetonius that he was a man of the most contemptible inactivity (contemptissimae inertiae). Such charge is easily explained on the ground that Clement found most of the duties of his office as consul so incompatible with Christian faith and practice as to render total abstention from public life almost an absolute necessity. In the case of Domitilla no doubt can remain, since De Rossi showed that the "Coemeterium Domitillae" (see EARLY CHRISTIAN CEMETERIES) was situated on ground belonging to the Flavia Domitilla who was banished for her faith, and that it was used as a Christian burial place as early as the first century. As a result of the accusations made against them Clement was put to death, and Flavia Domitilla was banished to the island of Pandataria in the Tyrrhenian Sea. Eusebius [Eusebius of Caesarea (d. c. 339), the first historian of the Church] (H.E., III, 18; Chron. ad an. Abrahami, 2110), the spurious acts of Nereus and Achilles, and St. Jerome (Ep., CVIII, 7) represent Flavia Domitilla as the niece, not the wife of the consul Flavius Clemens, and say that her place of exile was Pontia, an island also situated in the Tyrrrhenian Sea. These statements have given rise to the opinion that there were two Domitillas (aunt and niece) who were Christians, and latter generally referred to as Flavia Domitilla the Younger. Lightfoot has shown that this opinion, adopted by Tillemont and De Rossi and still maintained by many writers (among them Allard and Duchesne), is derived entirely from Eusebius who was led into this error by mistakes in transcription, or ambiguity of expression, in the sources which he used.