Protagorides the Historian (Προταγορίδης ὁ Ἱστορικός) was a historian from Cyzicus, a Greek city on the coast of Mysia in Asia Minor [1]. He is generally dated to the 4th century BCE, likely the latter part, based on the content of his work and the authors who cite him [1][2]. No details of his life or education survive.

His sole known work is On the Festivals in Cyzicus (Περὶ τῶν ἐν Κυζίκῳ ἑορτῶν), a text now lost [1][2]. It survives only in fragments preserved by later authors like Callimachus and Athenaeus. These fragments indicate the work detailed local myths, cultic practices, and the origins of festivals in his native city.

Protagorides represents the genre of local history (horography), focusing on the antiquities of individual city-states [1]. His work served as a source for later Hellenistic scholars studying local customs and aetiological myths. The fragments provide valuable, if minor, evidence for the religious and cultural history of Cyzicus, illustrating the vast number of such local historians whose works are almost entirely lost.

Sources 1. Brill's New Pauly (Brill): https://referenceworks.brillonline.com/entries/brill-s-new-pauly/protagorides-e1010160 2. Oxford Classical Dictionary (Oxford University Press): https://oxfordre.com/classics/view/10.1093/acrefore/9780199381135.001.0001/acrefore-9780199381135-e-5352