Born in Rusuccuru, Mauritania, Marciana was a young Christian girl who was beaten, tortured and handed over to gladiators as a sex toy during the persecutions of Diocletian; she brought one of the gladiators to Christianity. Accused of vandalising an idol of the goddess Diana, she was thrown to wild animals in the arena. She died around 303.
The manuscripts of the Acts do not agree on the date of martyrdom, January 9. Baronius, in his notes to the Roman Martyrology, estimates that July 12 marks a translation of relics and Jan 9, the anniversary of martyrdom.