The Histories
by Herodotus
4.2
Herodotus's account of the Greco-Persian Wars — from Croesus of Lydia through the Persian invasions of Greece, culminating in Marathon, Thermopylae, Salamis, and Plataea. Along the way, extensive digressions on Egypt, Scythia, Babylon, and the customs of peoples across the known world.
Check Price on Amazon (paid link)