The management of the nobles started with their collusion with Alexander

I don't think it is exaggeration to claim that the Achaemenid kingdom, as an exception, was the only professional and long-standing kingdom of the kings in Iran and even in the world who specialized in philanthropy and care of the people.

The overthrow of the Achaemenians

Most likely, the overthrow of the Achaemenians was a conspiracy of aristocrats who wanted to decide for their own money instead of paying taxes and did not feel any responsibility towards the society that was the main factor behind increasing the wealth of the aristocrats due to the features of pluralism.

The rule of the aristocracy as an entire body

The government, meaning the agent of ruling or force on the people, has always been in the hands of the aristocracy, who, since the time of Alexander, one of the grossest villains of the history, hired bullies and violent mobs to disturb the existing order (conspiracy of treason and rebellion) and at the same time to restrain the people, and this method was used over and over again later. The nobles were and are the main members of the body of bureaucrats.

When the executive-military apparatus of the existing government was saturated with corruption and tended in weakness and inefficiency, the expenses of the military force of the government or the factor of force on the people became unbearable for the nobles and the insecurity for theirs wealth reached its peak.

Then they, the aristocrats, hired new hungry mobs to overthrow the incompetent and high-spending mob and established a new government for the order and security of the aristocrat's wealth.

The management of these oppressive villains has always been with bureaucrats or aristocrats who played with the lion's tail or with these military bully villains, who sometimes have even caused danger to the lives of a few of these aristocrats or bureaucrats themselves too.

The Iranic hiroic chivalry period

The Parthians and Sassanids, who were of Sake (scythian) of Iranian descent, were warriors and bully but who had som kind of Iranic hiroic chivalry manner. The initial orientation of the Parthians for the Hellenes who had already left the Persian Union and came under the vigor of the Romans, over time gave way to a longing for the Achaemenid's way of kingship, and therefore, in the pursuit of reviving such a popular kingdom and their mature order, they searched for the intellectual basis of the Achaemenians, i.e. Mazdeyasnism. And the continuation of this path led to the transfer of power to the Sassanids.

The effort to collect the oral remnants of Achaemenid's culture, which was followed in the last half of the Parthian period and especially in the Sassanid period, and the conversion of these oral remains into writing, led to the emergence of the Avesta encyclopedias and among them the Gathas of Zarathustra himself, followed by inventing the script of "Din Dabireh", by which the initial pronunciation of the Gathas got possible.

Sassanid so called Zoroastrian religion

It was written down, but the meanings of records of Gathas were not available when the Pahlavi language (Parthian and Sassanid's language) has after some hundreds years of Parthian reign replaced the Ghathas language. What caused the foundation of the heresy of Sassanid so called Zoroastrian religion. In other words, it was a Sassanid invention that had got miles of distance from the original insight of the Mazdeyasnism.

On the other hand, Sassanid centralism along with Sassanid aristocracy not only changed the Achaemenid system but also introduced a new plan, which resulted in rigid class boundaries. The uprising of Mazdak was a reaction to this new design, which was welcomed by the Sassanid king at a first, but was later brutally suppressed and discredited by his crown prince, and from then on, the Sassanid dynasty became an "aristocratic" dynasty whose goal was to protect the best for the nobles. And being in the service of the nobility had become.

The long standing Islamic period

But the private interest of the elites caused separation and confusion among the same elites and instability among the people, and therefore the elites turned to collusion with the Romans and Arabs, which is another example of the same hiring of brutal and hungry fresh vilains who was less expensive, and thus the story of the 1400-years rule of Islam in the Middle East.