The early Greek Cynic, Diogenes, when asked where he came from simply replied: kosmopolits - 'I am a citizen of the world'. The ethical and political paradigm of cosmopolitanism is often exclusively attributed to the ancient schools of Cynicism and Stoicism. Cosmopolitanism is commonly assumed to have reached an impasse throughout the Middle Ages, only to resurface during the Enlightenment with the political philosophies of Hugo Grotius, Adam Smith, and Immanuel Kant. However, the political philosophy of Ab Nar al-Frb (870-950 CE), represents a promising avenue for the revival and expansion of cosmopolitanism. By harmonizing Plato and Aristotle with Neoplatonism and Islamic theology (kalm) in a radically innovative manner, al-Frb ambitiously proposes the existence of a political community extending across the entire inhabited world. This book demonstrates that the possibility and promise of al-Frb's cosmopolitanism remains an enduring contribution to contemporary debates concerning the future of democracy and global political association.