Teres, the father of Sitalces, was the first to establish the great kingdom of the Odrysians on a scale quite unknown to the rest of Thrace, a large portion of the Thracians being independent.

This Teres is in no way related to Tereus who married Pandion's daughter Procne from Athens; nor indeed did they belong to the same part of Thrace.
Tereus lived in Daulis, part of what is now called Phocis, but which at that time was inhabited by Thracians.

It was in this land that the women perpetrated the outrage upon Itys; and many of the poets when they mention the nightingale call it the Daulian bird.

Besides, Pandion in contracting an alliance for his daughter would consider the advantages of mutual assistance, and would naturally prefer a match at the above moderate distance to the journey of many days which separates Athens from the Odrysians.

Again the names are different; and this Teres was king of the Odrysians, the first by the way who attained to any power.
Sitalces, his son, was now sought as an ally by the Athenians, who desired his aid in the reduction of the Thracian towns and of Perdiccas.
Coming to Athens, Nymphodorus concluded the alliance with Sitalces and made his son Sadocus an Athenian citizen, and promised to finish the war in Thrace by persuading Sitalces to send the Athenians a force of Thracian horse and targeteers.