History of the Peloponnesian War

This Teres, the father of Sitalces, was the first that advanced the kingdom of the Odrysians above the power of the rest of Thrace.

For much of Thrace consisteth of free states. And Tereus that took to wife out of Athens Procne the daughter of Pandion was no kin to this Teres nor of the same part of Thrace. But that Tereus was of the city of Daulia in the country now called Phocis, then inhabited by the Thracians. And the fact of the women concerning Itys was done there; and by the poets, where they mention the nightingale, that bird is also called Daulias. And it is more likely that Pandion matched his daughter to this man, for vicinity and mutual succour, than with the other that was so many days' journey off as Odrysae. And Teres (which is also another name) was the first that seized on the kingdom of Odrysae.