Polemarchus (/ˈpɒlɪˌmɑːrkəs/; Greek: Πολέμαρχος; 5th century – 404 BC) was an ancient Athenian philosopher from Piraeus.
The son of Cephalus of Syracuse, Polemarchus had two brothers, the famous orator Lysias[1] and Euthydemus, and a sister who married Brachyllus.
[2] During the Athenian political upheaval in the late 5th century, Polemarchus was singled out by the Thirty Tyrants for being a wealthy metic.
After Polemarchus' death, the Thirty forbade his family from holding a funeral in any of their houses.
Plato's Republic is set at Polemarchus' house in the Piraeus, which was located next to their shield manufacturing store that employed 120 skilled slaves.