A person who practices, supports, or advocates for caesaropapism; someone who believes one ruler should control both government and religion.
From caesaropapism + -ist (suffix for 'one who practices'). This term identifies adherents of the ideology combining absolute political and religious authority.
Byzantine emperors were essentially caesaropapists by necessity—controlling both religion and politics was how they unified their vast, culturally diverse empire, though church leaders constantly complained about political interference in spiritual matters.
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