Today, "social policy" is an expression used across the globe to denote a broad range of issues, such as old age security, health, housing and so on. But historically, "social policy" had a distinct European origin and a distinct meaning. I maintain that "social policy" and the "welfare state" are more than a list of social services, and also have strong socio-cultural underpinnings that account for the diversity of social policy. The idea of "social policy" emerged in mid-nineteenth-century Germany against the backdrop of secularization and functional differentiation of modern society. I then pinpoint the twentieth-century move from "social policy" to the broader cultural idea of a universalistic "welfare state." The idea emerged internationally as early as the 1940s, even before the post-WWII rise of national welfare states, which, as I argue, differ according to national notions of "state" and "society." To this end, I compare the UK, Sweden, Germany, France, and two non-welfare states, the United States and the Soviet Union.