pridie idus januarias

• 49 B.C. — Caesar crosses the Rubicon (yet another suggestion).

• c. 230 A.D. — martyrdom of Tatiana in Rome

• c. 302 A.D. — martyrdom of Arcadius in Mauretania

pridie kalendas septembres

• 12 A.D. — birth of the future emperor Gaius (Caligula) at Antium
• 40 A.D. — Gaius (Caligula) celebrates an ovatio after his attempted military campaigns in Gaul and Britain
• 161 A.D. — birth of the future emperor Commodus (and his twin, Titus Aurelius Fulvus Antoninus)