Year 264 (CCLXIV) was a leap year starting on Friday (link will display the full calendar) of the Julian calendar. At the time, it was known as the Year of the Consulship of Gallienus and Saturninus (or, less frequently, year 1017 Ab urbe condita). The denomination 264 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.