The Bendidia was an ancient Athenian festival celebrating the Thracian goddess Bendis.It was celebrated on the 19th day of the month of Thargelion (late May, in the Gregorian calendar), and was introduced in 429 BC.[2] It was rare for ancient Athens to permit foreign residents of the city to worship their own gods; the cult of Bendis and the Bendidia is one of a few exceptions,[3] driven by the strategic importance of Thrace to Athens at the beginning of the Peloponnesian War.Worshippers coming from Athens processed from the Prytaneion, while the Thracian worshippers of Bendis in the Piraeus organised a separate procession, possibly organised so that it would join up with the Athenian contingent before they arrived at the sanctuary.[5] The horse race was followed by an all-night celebration, though the precise details of the remainder of the festival are unknown.