Less a Barrier Than a Surprise: Policing Everyday Commerce Along the 49th Parallel, 1880–1910

Abstract Between 1860 and 1930, the Canada-United States border emerged as a crucial economic boundary. In creating the border, however, Canada and the United States prioritized revenue generation over coherence or uniformity. This priority created an unpredictable barrier for both businesses and individuals. Consuls often focused their attention on understanding the impacts of tariffs, trade volume, and smuggling on transnational commerce. The border’s practical impacts, however, went far deeper. For individuals, the border’s unpredictability shaped everything from how they gave gifts to the ways they supported their families. For businesses, the border impacted profit margins and intellectual property. But it also changed how businesses approached administrative tasks—everything from staff training to who they delegated to fill out paperwork. Although imagined as a federal project, the border’s tolerances for variation ensured that regional and local solutions proliferated. Federal mandates merged with local interests to create an inconsistent barrier of ever-changing heights.