In the closing half of the nineteenth century Argentina experienced a string of cholera epidemics like so many other parts of the world. The epidemics arrived at a point in time in which the Argentine state, based in the national capital of Buenos Aires, worked with the provincial governments to establish the modes of governance that straddled the thin line between centralized control and provincial autonomy. The talk explores this process through the topics of epidemic disease, public health, the medicalization of nineteenth-century Argentine society, and the notion of uncertainty. It shows that in contrast to other more common topics within the field of state-building/formation studies, such as war and high politics, a new disease required a continual process of negotiation and adaptation between national and provincial officials as the state struggled to create the organizational structures to respond to the disease in the Argentine provinces.