Wikipedia
The gens Flavia was a plebeian family at Rome. Its members are first mentioned during the last three centuries of the Republic. The first of the Flavii to achieve prominence was Marcus Flavius, Tribune of the plebs in 327 and 323 BC; however, no Flavius attained the consulship until Gaius Flavius Fimbria in 104 BC. The gens became illustrious during the first century AD, when the family of the Flavii Sabini claimed the imperial dignity.
Under the Empire, the number of persons bearing this nomen becomes very large, perhaps due to the great number of freedmen under the Flavian dynasty of emperors. It was a common practice for freedmen to assume the nomina of their patrons, and so countless persons who obtained the Roman franchise under the Flavian emperors adopted the name Flavius, which was then handed down to their descendants.
During the later period of the Empire, the name Flavius frequently descended from one emperor to another, beginning with Constantius, the father of Constantine the Great. The name became so ubiquitous that it was sometimes treated as a praenomen, to the extent of being regularly abbreviated Fl., and it is even described as a praenomen in some sources, although it was never truly used as a personal name. The last emperor to take the name was eastern emperor Constantine IV.
After the name fell into disuse among the Byzantine emperors, it was used as a title of legitimacy among the barbarian rulers of former Roman provinces, such as Spain, where the Visigoths and their Spanish successors used the title ″Emperor of All Spain″, and the kings of the barbarian successor kingdoms of Italy, such as the Ostrogoths and the Lombards also used it, with a special meaning as the ″protector″ of the Italian peoples under Lombard rule.
The vast majority of persons named Flavius during the later Empire could not have been descended from the Flavia gens; and indeed, the distinction between nomina and cognomina was all but lost, so that in many cases one cannot even determine with certainty whether it is a nomen or a cognomen. However, because it is impossible to determine which of these persons used Flavius as a gentile name, they have been listed below.
Flávia is a Portuguese-language girl's name. It is the equivalent of Flavia (name) found in Italy and Spain.
Saint Flavia is a saint of the Roman Catholic Church. She was martyred at Messina along with her brother, the Benedictine monk Saint Placidus, their brothers Eutychius and Victorinus, Donatus, Firmatus the deacon, Faustus, and thirty other monks. They were killed by pirates. Their feast day is October 15.
Flavia is an Ancient Roman name meaning “blonde” from the Latin word “flavus”, meaning “golden, blonde”. It is a feminine form of the Roman family name Flavius. The name is most commonly used in Italy, Romania, Brazil ( Portuguese: Flávia) and in Spanish-speaking countries. It is rarely used in the United States, but was given to 11 newborn American girls in 2010 and 12 American girls born in 2011.
The Portuguese and Brazilian spelling of the name is Flávia.
Flavia is the name of Roman Catholic and Eastern Orthodox saints: Flavia Domitilla and Flavia. It was also the name of Princess Flavia, a major character in Anthony Hope's 1894 novel The Prisoner of Zenda and its sequel Rupert of Hentzau. It is also the name of Flavia de Luce, the 11-year-old sleuth who stars in Alan Bradley's mystery series that began with The Sweetness at the Bottom of the Pie in 2009.