Dacian or Dacianus was the prefect of Gaul under Diocletian and Maximian and acted in Hispania Tarraconensis or Hispania Carthaginensis at about the same time. He caused the martyrdom of, amongst others, Saint Faith, Caprasius of Agen, Vincent of Saragossa and Eulalia of Barcelona.
- Alban Butler, "The Lives of the Fathers, Martyrs, and Other Principal Saints, Volume 10", p.139-140
- "The Roman Breviary: Reformed by Order of the Holy Oecumenical Council of Trent: Published by Order of Pope St. Pius V.; and Revised by Clement VIII. and Urban VIII.; Together with the Offices Since Granted, Volume 1", p.978
- Cotman, John Sell. Engravings of Sepulchral Brasses in Norfolk..., Bohn, 1838, p.48
- "Virginmartyr Eulalia of Barcelona", Orthodox Church in America