Religion has been used in politics since it came to be!

Rulers since ancient times have used religion as a basis to justify their rule, some even deemed themselves as their reincarnation, or god themselves.

One such way in which religion was used in politics was the when the sassanids took the throne from the parthians in 224 AD. To justify their forcefully taken throne they used Zoroastrianism.

To prove that their rule was indeed justified the ruler ardasid I reasoned that the parthians had lost the true Zoroastrianism religion after the influence of greek culture due to Alexander's invasion, and sassanids brought the religion back from decay.

Such reasoning and making Zoroastrianism, (which was the popular religion in the region) the state religion, brought the newly found empire justification to the throne. And thus began the story of another great empire of its time.