The medieval Islamic world from the decline of the early empire and the fall of Baghdad to the flourishing commonwealth during the lifetime of Ibn Khaldun. This course surveys key developments in religion, politics, and society across the Middle East from the 11th century up to the 15th century CE. Starting with the situation on the eve of the Crusades, we trace broader patterns in Islamic history through the emergence of various sultanates (including the dynasty of Salah al-Din Ayyubi and the Mamluks) as well as regional dynamics from North Africa and Spain in the West to Iran and India in the East.