ante diem iii idus decembres
- Agonalia — the fourth and final occurrence of this festival in the Roman calendar; like all instances, the Rex Sacrorum would sacrifice a ram in the Regia, but on this occasion, the sacrifice was apparently in honour of Sol Indiges.
- Septimontium — a somewhat obscure festival apparently originally only celebrated by the ‘montani’ (i.e. the ‘hill-dwellers’) which involved sacrifices on each of Rome’s seven hills.
- 287 — martyrdom of Fuscian (and others)
- 302 — martyrdom of Pontian