This book traces how Armenian migrants changed the demographic and cultural landscape of Istanbul and Western Anatolia in the course of the seventeenth century. During the centuries that followed, Ottoman Armenian merchants, financiers (sarrafs), authors, musicians, translators, printers and bureaucrats would play key roles in Ottoman trade, cultural life and even governance, that is, in most spheres of the empire's economic and cultural life. This book shows how that cosmopolitan world came into being. Using both Ottoman Turkish and little-known Armenian sources, Henry Shapiro provides the first systematic study of Armenian population movements that resulted in the cosmopolitan remaking of Istanbul. In the first part of the book he documents the Great Armenian Flight, showing how the global crisis of the seventeenth century (war, climate change, famine) impacted the historical Armenian population centres of the Caucasus and Eastern Anatolia and led to mass migrations and resettlement in Western Anatolia, Istanbul and Thrace. In the second part of the book Shapiro links this history of migration and the refugee crisis with the development of intellectual and cultural life in Istanbul and Western Anatolia - the rise of the Western Armenian Diaspora.