Chosen 29th pope. Enlarged the catacombs. Reigned at the start of the persecution of Diocletian, and was himself martyred. Legend says that he apostatized, made sacrifice to pagan gods, then repented, and was beheaded, but this story has been discredited.
- Book of Saints, by the Monks of Ramsgate
- Lives of the Saints, by Father Alban Butler
- New Catholic Dictionary
- Our Sunday Visitor’s Encyclopedia of Saints
- Pictorial Lives of the Saints
- Roman Martyrology, 1914 edition
- “Pope Saint Marcellinus“. Saints.SQPN.com. 15 March 2014. Web. 17 March 2014. <>