This chapter briefly surveys the intellectual history of modern, western counterinsurgency theory, as conservative, high modernist utopianism. It sets out concise and synoptic evidence for the argument, which serves as context for the later case chapters. I focus on counterinsurgency manuals—applied theoretical texts written by counterinsurgency practitioners, aiming to shape battlefield and political conduct. Manuals link theory and practice, connecting idealized military and political theory to the history of on-the-ground conduct. My approach is primarily contextualist. Proceeding chronologically, I draw connections and contrasts between canonical manuals, from the early modern period to the present. While small wars or counterinsurgency manuals were conservative from early on, high modernism and utopianism emerged only gradually and incidentally, taking multiple forms. I show how ideas cross-pollinated across texts, accumulating scattershot political idealizations and military practices alike. In so doing, I link micro-level individual intellectual change with larger historical processes, at the global level.