This group of saints includes actually two groups. The First group of Ss. Severus, Severian, Carpophorus, and Victorinus. According to the Passion of St. Sebastian, the four saints were soldiers who refused to sacrifice to Aesculapius, and therefore were killed by order of Emperor Diocletian, two years after the death of the five sculptors [mentioned next]. The bodies of the martyrs were buried in the cemetery of Santi Marcellino e Pietro on the fourth mile of the via Labicana by Pope Miltiades and St. Sebastian (whose skull is preserved in the church).
The second group is composed of the five sculptors: Ss. Claudius, Castorius, Symphorian, Nicostratus, and Simplicius. The second group was killed in Pannonia. They refused to fashion a pagan statue for Emperor Diocletian or to offer sacrifice to the Roman gods. The Emperor ordered them to be placed alive in lead coffins and thrown into the sea in about 287. Simplicius was killed with them. According to the Catholic Encyclopedia:
The Acts of these martyrs, written by a revenue officer named Porphyrius probably in the fourth century, relates of the five sculptors that, although they raised no objections to executing such profane images as Victoria, Cupid, and the Chariot of the Sun, they refused to make a statue of Æsculapius for a heathen temple. For this they were condemned to death as Christians. They were put into leaden caskets and drowned in the River Save. This happened towards the end of 305.
