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 integration of immigrants into the society of the host country is a question of substantial importance for both research and policy. Religion is often seen as a barrier in this context. This paper contributes to the debate by studying Danish migrants emigrating to the U.S. during the age of mass migration, who are generally described as having integrated exceptionally rapidly. While Denmark is usually conceived as a very homogeneous country, during this time period a religious conflict pitted Grundtvigians against the evangelical ‘Inner Mission’ movement; a conflict which played out even more strongly within the Danish communities in the U.S. than in Denmark. We use this unique historical setting to investigate the role of religion, and especially of religious conflict, for the integration and economic success of migrants. Grundtvigian communities focused on preserving Danish culture and tradition, whereas Inner Mission communities argued for assimilation into American society. We investigate whether followers of Inner Mission were trying to assimilate more than members of other Danish communities and whether they were economically more successful. We present descriptive evidence as well as an instrumental variables approach, instrumenting for the location of Inner Mission churches. We are thereby able to draw conclusions on the role of religious institutions for integration and demonstrate that they need not be a barrier.