From the 1911 Columbia Encyclopedia:
PAEONIUS, of Mende in Thrace, a Greek sculptor of the latter part of the 5th century. The statement of Pausanias that he executed one of the pediments of the temple of Zeus at Olympia is rejected by critics. But we possess an important work of Paeonius in the Victory found in the German excavations at Olympia, and set up, according to the most probable view in meniorv of the hstll~ of Snhscferi~ (sP Gprsv Aisr fig. 36). It bears the inscription Dedicated to Olympian Zeus by the Messenians and Naupactians as a tithe of the spoil of their enemies. Paeonius of Mende made the statue, and was a successful competitor in the construction of the gable-figures for the temple. The gable figures last mentioned were doubtless gilt victories of bronze which stood on the gable, not in it. Pausanias seems to have misunderstood the phrase as implying that Paeonius made one of the pedimental groups.
From Harper's Dictionary of Classical Antiquities (1898):
(Paiônios). (1) A Greek sculptor of Mendé in Thrace. About B.C. 436 he was employed in the decoration of the temple of Zeus in Olympia. According to Pausanias (v. 10 6), he was the sculptor of the marble groups in the front, or eastern, pediment of the temple, representing the preparations for the chariot-race between Pelops and Oenomaüs. (See Olympia.) Important portions of these have been brought to light by German excavators. He was also the sculptor of the figure of Niké, more than life-size, dedicated by the Messenians (Pausan. v. 26 1), which has been restored to us by the same means. With the exception of the head, it is in fairly good preservation.