The Persian Empire was enormous. The greatest ruler they had was a man named Cyrus I, or Cyrus the Great

Cyrus the Great conquered people and followed these rules:
1. Treat people with tolerance
2. Let them govern themselves as long as they follow certain rules
3. Let them worship their gods freely

They also created a road system to improve communication

After Cyrus died, his son Darius I took over. The smartest thing that he did was not to change anything his father did. Unfortunately, the great-grandson of Darius I was Darius III, who we know from Greece, ruined the entire Persian Empire

The Persians had a religious philosophy that other religions copied, 'The world is a battleground for good and evil. On Judgment Day, everything will be sorted out."

This religion was called Zoroasterism.