Year
46 BC was the last year of the
pre-Julian Roman calendar. At the time, it was known as the
Year of the Consulship of Caesar and Lepidus (or, less frequently,
year 708 Ab urbe condita). The denomination 46 BC for this year has been used since the early medieval period, when the
Anno Domini calendar era became the prevalent method in Europe for naming years. This year marks the change from the
Numan calendar to the
Julian calendar. The Romans had to periodically add a leap month every few years to keep the calendar year in sync with the
solar year but had missed a few with the chaos of the civil wars of the late republic.
Julius Caesar added two extra
leap months to recalibrate the calendar in preparation for his calendar reform, which went into effect in
45 BC. This year therefore had 445 days, and was nicknamed
annus confusionis ("year of confusion").