The Testament of Darius (who ruled Persia from 522 to 486 B.C.E.) to his son and successor Emperor Xerxes the Great:
As I am about to depart this world, twenty-five countries are part of the Persian Empire. In all of these countries, Persian currency is accepted, and Persians enjoy a particular respect in these countries. My successor, Khashyar Shah must, like me, work to retain these countries. And the way to retain them is to not interfere in their internal affairs, and to respect each country’s religion and ritual.
As I am about to depart this world, you have twelve koroure in gold in the royal treasury; this gold is one of the pillars of your power. A king’s power is not just dependent on the sword, but on wealth as well. Remember that you must add to this treasury and not diminish it. I am not suggesting that under dire circumstances, you should not take gold out of it, as the rule for this treasury gold is that it must be used when necessary, but at first chance, return what you have taken to the treasury. I am indebted to your mother Atousa, so you must, at all times, ensure her happiness and peace of mind.
For ten years, I have been busy building grain silos all around the country. I learned the method of building these cone-like stone structures in Egypt, and since the silos are intermittently emptied, insects do not thrive there and grain can be stored in these silos for several years without rotting. And you must continue the work of building these silos until the time when they can hold two to three years’ reserve for the whole country. And each year, after the harvest, use the stored grain to eliminate shortages and replenish the silos after harvesting and this way, you shall never worry about foodstuff in this country, even if you face two or three years of draught.
Never appoint your friends, or intimate servants to governmental posts, since for them the privilege of your friendship should suffice. If you appoint your friends and servants to governmental posts, and they inflict injustice on the people, and abuse their position, you will be unable to punish them, since they are your friends, and you must bear in mind this friendship.
The canal I wanted to build between the Nile and the Red Sea is not yet finished, and finishing this waterway is very important from the perspective of the military and commerce. You must finish this canal, and the fees for passage of ships must not be so steep that captains will prefer avoiding it.
I have sent an army to Egypt with the task of bringing law and order to that land; I still have not had the chance to send a force to Greece. You must finish this work. Attack the Greeks with a powerful army, and make the Greeks understand that the Persian king has the power to punish those who commit atrocities.
My other recommendation to you is that you should never allow sycophants and liars in your entourage, since they are both plagues to monarchies; you should ruthlessly turn away all liars.
Never allow government bureaucrats to have dominion over the populace; in order to prevent such domination, I have passed tax laws, and limited the contacts between the people and bureaucrats; if you preserve these laws, the contacts between the people and government officials will be minimal.
Keep officers and soldiers of your army content, and never mistreat them. If you mistreat them, they cannot respond in kind, but instead, they will take their revenge in the theater of war, even if such revenge costs them their lives; their revenge will take the shape of inaction and surrender, and through this they prepare the ground for your defeat.
Continue the education reforms that I began, and allow your subjects to learn how to read and write and increase their intelligence; the more intelligent they are, the more you can rule with an easy mind. Always defend the faith of worshiping Yazdan, but never force any group to follow your faith, and always bear in mind that everyone should be free to pursue whatever faith he or she desire.
When I bid farewell to life, wash my body, and enwrap me in the shroud I have prepared, and put me in a coffin made of stone and place me in my grave. But do not cover my grave, thus allowing yourself the chance to occasionally come to the tomb and see my stone coffin, and remind yourself that there lies my father, a man who authoritatively ruled over twenty five countries, and now he is dead, and I too shall one day die like him.
It is human fate to die, and it makes no difference whether you are a king of twenty-five countries or a poor wood-gatherer, and no one remains eternally in this world. If you do not visit my tomb every time you have a chance and see my coffin, pride and selfishness will overcome you, but when you are near your death, order them to close my grave, and then in your will, ask your son to keep your grave open so that he can see the coffin holding your body.
Never, never be a judge and a prosecutor in the same case, and if you have a claim against someone, ask an impartial judge to adjudicate the case, and issue a judgment. Since if someone who is the claimant is also the judge, he will invariably commit injustice.
Never cease the work of developing the country. If you cease the work of development, the country will inexorably fall into a state of disarray. It is a rule that a country that is not improving falls into desolation. In the work of developing, the construction of new aqueducts. (ghanats), the building of new roads and the establishment of cities must be giving top priority.
Never forget forgiveness and generosity and know that after justice, the highest quality for a king is forgiveness and generosity. But mercy must be offered when the injustice has been committed against you; if the offender has committed an injustice against someone else and you pardon the crime, you have committed an injustice yourself, for you have ignored someone else’s rights.
I will say no more. I have made these statements in front of those who are now, in your absence, in attendance; I want them to know that I have made these suggestions before my death, and now to leave me alone, as I feel the hour of my death is near... King Darius