We study the political effects of mass emigration to the United States in the nineteenth century using data from Sweden. To instrument for total emigration over several decades, we exploit severe local frost shocks that sparked an initial wave of emigration, interacted with within-country travel costs. Our estimates show that emigration substantially increased the local demand for political change, as measured by labor movement membership, strike participation, and voting. Emigration also led to de facto political change, increasing welfare expenditures as well as the likelihood of adopting more inclusive political institutions.

We exploit exogenous variation arising from the historical rollout of the Swedish railroad network across municipalities to identify the impacts of improved transport infrastructure on innovative activity. A network connection led to a local surge in patenting due to an increased entry and productivity of inventors. As the railroad network expanded, inventors in connected areas began to develop ideas with applications outside the local economy, which were subsequently sold to firms along the network. Our findings suggest that reductions in communication and transportation costs were an important driver of the historical emergence of a market for ideas.