As my new book Islam, Authoritarianism, and Underdevelopment: A Global and Historical Comparison explains, there existed a certain level of separation between religious and political authorities in the first four centuries of Islamic history.That is why the first systematic book about “Islamic” politics was written as late as the mid-eleventh century. It was Mawardi’s The Ordinances of Government. The book argues that an Islamic government is based on a caliph (an Arab man from the Quraish tribe) to rule all Muslims. The caliph holds the entire political and legal authority and stays in power for life. The caliph delegates his legitimate authority to sultans, governors, and judges.The second book, which systematically defines an Islamic political system, was written in the early fourteenth century. It is Ibn Taymiyya’s Sharia-based Governance in Reforming Both the Ruler and His Flock. Instead of the one-man rule of a caliph, this book emphasizes the alliance between the ulema and the state authorities. Ibn Taymiyya interprets the only phrase in the Quran about authority, “uli’l-amr” (4:59), as referring to the ulema and the rulers (though other scholars have interpreted it differently).