Here's a good podcast documentary on the Iranian revolution by The Rest is History
Why did the Iranian Revolution erupt in 1979? What was the nature of the relationship between President Carter and the ostentatious Shah Mohammad Reza Pahlavi? And, who was the Ayatollah Ruhollah…
pca.st
The short story is that in the shah's Iran Imam's were also legal and administrative functionaries. Especially out in the country where people were illiterate. When the shah tried liberal reforms, that was good for the people, but weakened the power of the imams, that's when they suddenly started caring about the shah's corruption, human rights abuses and unwise management of govornment funds.
The shah's greatest flaw was that of incompetence. He was a weak ruler. He inherited power from his father. But had none of his fathers talents. He failed to correctly identify what and who kept him in power. His rule was nothing but a string of bad decisions