Ghervas traces European efforts to create peace settlements, starting with the Treaty of Utrecht in 1713 and moving through the Congress of Vienna in the nineteenth century, the League of Nations and the negotiations to temper the Cold War in the twentieth century, and discussions within today’s enlarged European Union. Any historical narrative of this scale can seek to answer only big questions—in this case: What brought about peace and allowed settlements to endure? Hundreds of books, many of them classics, have addressed that puzzle. Some stress the rise and fall of totalitarian alternatives to liberal democracy; others, the changing nature of economic interdependence, the diffusion of political and social welfare rights, the spread of national self-determination, the rising destructiveness of military technology, the role of hegemonic powers, or the design of international legal institutions. In such august and crowded company, this book’s interpretation remains frustratingly opaque. At times, the author seems to be a Hegelian, explaining each settlement as the result of a corresponding (if often ill-defined) “spirit” of the age. Yet sometimes, she takes a view more grounded in pragmatism, arguing that narrow functional interests and responses to immediate events dictated policy. And elsewhere, she rejects the search for historical lessons entirely.