We consider the impact of non-violent religious conflict on productivity during a period of industrialization. We zoom in on a Protestant and otherwise very homogeneous country: early twentieth century Denmark. We construct a rich microlevel dataset of 964 butter factories (creameries), the main catalyst of the industrial revolution in Denmark, during which two rival pietist movements fought for the hearts and minds of Danes. The Inner Mission, in contrast to the Grundtvigians, argued that creameries should be closed on Sundays in accordance with the Third Commandment. We combine our creamery data with various proxies for the strength of this rivalry, finding it to be associated with lower productivity. Moreover, we argue for a causal impact of this conflict on productivity through the exploitation of exogenous variation based on locations where one of the central figures of the Inner Mission, Carl Moe, preached. Finally, we provide evidence that this impact of the Inner Mission on productivity came through conflict.

The cultural assimilation of immigrants is often linked to economic success, with religion seen as a barrier. We examine the role of ethnic enclaves and churches in the assimilation of Danish Americans using a difference-in-differences approach. A religious schism in 1883 split the community into "Happy" Danes, who prioritized cultural preservation, and "Holy" Danes, who emphasized assimilation. Using US census data and Danish American church and newspaper archives, we find that Danes in counties with Happy churches chose more Danish names for their children, while newspapers associated with Holy Danes Anglicized more rapidly. Despite these differences in cultural assimilation, we find little difference in occupational outcomes. If anything, Happy Danes performed slightly better in the labor market, despite being less assimilated. This suggests that cultural preservation need not hinder economic success, challenging conventional assumptions about the trade-off between assimilation and economic integration.

From the late 19th century until the advent of antibiotics, tuberculosis (TB) transitioned from a leading cause of death to a relatively moderate one in most now-developed countries. Knowing the factors that contributed to this decline is crucial for understanding the historical mortality transition itself. This paper examines the establishment of TB sanatoria in 95 major European cities between 1880 and 1910. Although sanatoria provided rest and healthier diets for patients, there was no effective therapeutic treatment of tuberculosis, and the primary impact of a sanatorium on TB transmission was the isolation of infected individuals. On average across Europe, we find that sanatoria reduced TB mortality by 10 percent and accounted for 30 percent of the decline in TB mortality rates from 1880 to 1910.