PANIO´NIA
PANIO´NIA (πανιώνια), the great national panegyris of the Ionians on Mount Mycale, near Priene and between Ephesus and Miletus (from which Grote conjectures that these towns were the primitive centre round which the other Ionian settlements gathered, forming gradually the confederation of twelve cities), where their national god Poseidon Heliconius had his sanctuary, called the Panionium (Hdt. 1.148; Strabo viii. p.384; Paus. 7.24.4). One of the principal objects of this national meeting was the common worship of Poseidon, to whom splendid sacrifices were offered on the occasion (Diod. 15.49). As chief priest for the conduct of the sacrifices, they always appointed a young man of Priene, with the title of king. But religious worship was not the only object for which they assembled at the Panionium; on certain emergencies, especially in case of any danger threatening their country, the Ionians discussed at these meetings political questions, and passed resolutions (Hdt. 1.141, 170), as was usual at an amphictyonic panegyris [see PANEGYRIS].Diodorus (15.49) says that in later times the Ionians used to hold their meeting in the neighbourhood of Ephesus instead of at Mycale. Strabo, on the other hand, who speaks of the Panionic panegyris as still held in his own time, not only does not mention any such change, but appears to imply that the panegyris was at all times held on the same spot, viz. on Mount Mycale. Diodorus therefore seems to consider the Ephesian panegyris [EPHESIA] as having been instituted instead of the Panionia. But both panegyreis existed simultaneously, and were connected with the worship of two distinct divinities, as is clear from a comparison of two passages of Strabo viii. p.384, xiv. p. 639. The truth probably is that the more splendid festival of the Ephesia attracted a larger concourse than the real Panionia and threw it in later times into the shade; and although the old festival continued, yet as early as Thuc. 3.104 the Ephesia was looked upon as the representative Pan-Ionic gathering.
(Compare Tittmann's Griech. Staatsv. p. 668, &c.; C. F. Hermann, Lehrb. der Gottesd. Alterth. § 66, n. 2, 3; Grote's Hist. of Greece, iii. p. 229 ff.)