Year 451 BC was a year of the pre-Julian Roman calendar. At the time, it was known as the Year of the Consulship of Sabinus and Augurinus and the First year of the decemviri (or, less frequently, year 303 Ab urbe condita). The denomination 451 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.