Early investments in state capacity promote persistently higher levels of social capital

Significance Understanding the factors that influence social capital formation is of great interest to social scientists and policy makers. In this paper, we make two contributions to our understanding of its origins. First, using a series of historical and contemporary measures of social capital, we show that early investments in state capacity, as measured by the spatial expansion of the federal postal network in the United States, strongly predicts higher contemporary levels of social capital. Second, we show the existence of an important informational channel through which early investments in state capacity persisted. Namely, the spread of the postal network strongly predicts the location of local newspapers. These findings indicate that the recent declines in local newspapers may harm social capital.