Abstract
Starting from the historical work of Memnon’s of Heracleia, which has been handed down to us by Photius’ excerpta, we can reconstruct the role of the polis of Heracleia Pontica, in the complex historical period after Alexander’s III death. With this paper, I will analyse the tyrannical period, and in particular Dionysius’ tyranny. During his tyranny, Dionysius of Heracleia Pontica was able to realize a complex network of relationships; he succeeded in making the city an undisputed protagonist of that historical period. He knew how to juggle the struggles among the Diadochoi and he was able to forge relations with some of them, and with some poleis of the Black Sea area, like Sinope, aiming to increase his power and that of his homeland.