255

Year 255 (CCLV) was a common year starting on Monday of the Julian calendar. At the time, it was known in Rome as the Year of the Consulship of Valerianus and Gallienus (or, less frequently, year 1008 Ab urbe condita). The denomination 255 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.