How politically significant has religion been across different societies, historical periods, and religious traditions—and how does its political significance in the contemporary world compare?

Historically, religion and politics were rarely, if ever, conceptually or practically separated. Across almost all pre-modern societies, empires, and civilisations, religious authority and political legitimacy were profoundly intertwined. Monarchs ruled by divine right, while both the Ottoman and Holy Roman empires were structurally organised around religious identity, with religious institutions [...]