 Although ultimately ending in failure at the Battle of Marathon, Darius succeeded in the re-subjugation of Thrace, expansion of the empire through the conquest of Macedon, the Cyclades and the island of Naxos and the sacking of the city of Eretria.Darius organized the empire by dividing it into provinces and placing satraps to govern it.He organized Achaemenid coinage as a new uniform monetary system, along with making Aramaic the official language of the empire.