At one point in antiquity, the Achaemenid Persian Empire was the largest empire the world had ever seen, but aside from its role in the Greco-Persian Wars and its collapse at the hands of Alexander the Great, it has been mostly overlooked. When it has been studied, the historical sources have mostly been Greek, the very people the Persians sought to conquer. Needless to say, their versions were biased.
It was not until excavations in the region during the 20th century that many of the relics, reliefs, and clay tablets that offer so much information about Persian life could be studied for the first time. Through archaeological remains, ancient texts, and work by a new generation of historians, a picture can today be built of this remarkable civilization and their most famous leaders.
When considering this empire’s rulers, the two most often referenced are Xerxes, the leader of the Persian invasion of Greece which caused the heroic sacrifice of the Spartans and their allies at Thermopylae, or Cyrus the Great, the man who created the empire. While he was one of the most influential men in the ancient world, research on Cyrus the Great is simultaneously fascinating and frustrating. The Persians’ ancestors did not write (in fact, in their epic poems and myths, they claim that it was something taught to man by demons and therefore something to be avoided), and though the Iranians had taken up writing in their governmental and administrative functions by the time Cyrus lived, the kings still did not learn to write. Put simply, it was considered a functional skill, but not of the greatest importance.
As a result, while plenty of ancient sources mention the great Persian king, Persian sources themselves are rare, and those sources that do exist, such as the Babylonian Chronicle, are largely dry and state only the basic facts and large events.