[Verginius Rufus]

The Athenian general Cimon, son of Miltiades, had a Thracian mother--his grandfather was a Thracian king named Olorus. Miltiades was credited with the Athenian victory at Marathon, and Cimon was important enough for Plutarch to write a biography of him.

The historian Thucydides was the son of a man named Olorus, but whether that means Thucydides had Thracian ancestry is uncertain. Possibly he was related somehow to Cimon. But his father's name could just mean that his grandfather had ties of friendship with the Olorus who was king in Thrace (but not of all of Thrace).

[SunkenCiv]

The Thracians (including Thracian cavalry) were also in Alexander the Great’s army when he thrashed (heh) the Persian army at the Granicus, despite inferior numbers.