We study the impact of the 1918 influenza pandemic on short- and medium-term economic performance in Sweden. The pandemic was one of the severest and deadliest pandemics in human history, but it has hitherto received only scant attention in the economic literature – despite representing an unparalleled labour supply shock. In this paper, we exploit seemingly exogenous variation in incidence rates between Swedish regions to estimate the impact of the pandemic. The pandemic led to a significant increase in poorhouse rates. There is also evidence that capital returns were negatively affected by the pandemic. However, contrary to predictions, we find no discernible effect on earnings.