Dionysius I of Syracuse
In the early fourth century BC the situation drastically changed when Dionysius I of Syracuse and the Lucanians threatened the Greek cities of Southern Italy. With the exception of Locri, which was an ally of Dionysius, the cities formed an alliance called the Italiote League in 393 BC. Wonder thinks Sybaris on the Traeis probably was a member of the league together with Croton, Caulonia, Thurii, Rhegium and Velia by 389 BC.