In the late nineteenth and early twentieth centuries, millions of people moved into and out of the Ottoman Empire, sometimes voluntarily and sometimes under extremely violent circumstances. More often than not, they moved in groups that were religiously defined. This course examines how these developments shaped the future of the modern Middle East, Balkans, and beyond. Questions include: How did migration and the idea of the nation shape each other? What does it mean to call a group or a migration "religious"? Why did certain types of diversity become a "problem," in the eyes of the state? What caused these population displacements? What can this topic teach us about today's mass migrations?