This chapter examines the role of crisis in the history of economic thought. It explores what is often called the first major crisis of capitalism: the Long Depression of the late nineteenth century. Characterised paradoxically by deflation and falling profits, alongside rising industrial output and real wages, the chapter queries whether this period truly constituted a crisis and what this may tell us about understanding historical crises. It situates the Long Depression within broader intellectual context, focusing on the emergence of marginalist economics. It examines what the field of economics can and cannot tell us about broader dynamics of empire, class conflict, and its blindspots in understanding capitalism’s crisis dynamics up to the present day.