Son of Saint Tranquillinus of Rome who raised him a pagan before his own conversion. Twin brother of Saint Marcellian. Convert to Christianity. May have been a deacon. Imprisoned for his faith during the persecutions of Maximian Herculeus. Visited in prison by Saint Sebastian who encouraged him not to give in. Martyr.
- nailed to a post and pierced with a lance in 286
- buried near the Catacomb of Saint Domitilla
- grave re-discovered in 1902
- “Saint Mark“. CatholicSaints.Info. 8 June 2013. Web. 6 May 2015. <>