ante diem v idus januarias
- Agonalia — one of four dies agonales during which the Rex Sacrorum would sacrifice a ram in the Regia; on this occasion apparently in honour of Janus.
- 250 A.D. — martyrdom of Felix and companions in Africa
- 302 A.D. — martyrdom of Julian and companions at Antioch
- c. 303 A.D. — martyrdom of Marciana at Caesarea (Mauretania)