I remember this episode, though not too many details. However, the Memory-Alpha wiki is usually a good resource on all things Trek, and it writes that Tanagra is a location on Shantil III and not the site in Boetia.

Were it to be a reference to the events that occurred there in the Peloponnesian War, we would have a serious continuity error. The entire point is that the phrase references a mytho-historical event from the culture's past; how in the world would the Shantil III natives know about ancient Greece? That's like Spock sharing the ancient Vulcan tale of Julius Caesar's rise to power and how Octavian became the first Roman emperor. I've changed that section of the article for now.

As for actual leaders, Thucydides lists two Athenian commanders: "Hipponicus, son of Callias, and Eurymedon, son of Thucles"