Time, Festivals, and the Ἐννεατηρίς in Archaic and Classical Greece

From the sixth through the mid-fourth century BCE, many Greek communities used an eight-year cycle or ἐννεατηρίς (literally “nine-year,” by inclusive Greek reckoning) to intercalate civil calendars, which were lunar in nature. Such calibration kept lunar calendars aligned with the longer solar year. This study, the first article on the enneatēris in its own right, has two aims: to assemble evidence from across the Greek world for the enneatēris, and to demonstrate how the enneatēris helped coordinate local, regional, and Panhellenic calendars through interlocking festival rites. New documentary evidence allows us to understand this more clearly than ever before, and to make sense of an important social, religious, and astronomical mechanism by which individuals and communities reckoned time and ensured that local calendars maintained synchronicity with one another and with the seasons. The study bridges work on early Greek scientific knowledge and socioreligious institutions, while transcending modern distinctions between the two realms of discourse.