Since the 1970s, the gap between Islamic countries and the rest of the world has continuously widened. Whereas elsewhere the share of democratic regimes has strongly increased, in the Islamic world it has decreased and attempts at democratization – most recently during the Arab Spring – have largely failed. Regarding human rights – e.g. gender equality, gay rights and the rights of religious minorities – Islamic countries continue to have a worse track record than other parts of the world. Civil wars and terrorism have increased not only in number and intensity worldwide, but increasingly involve radical Islamist groups and are fought out within and on the edges of the Muslim world. Economically, most countries of the Islamic world have fallen not only further behind the industrialized West but also behind non-Islamic ascending economies in East Asia and Latin America. We discuss the evidence for this deepening crisis of the Islamic world and explore potential causes, including Western imperialism, the relation between state and religion in Muslim countries, and the rise of religious fundamentalism.