This article examines debates over banking regulation in Germany that culminated in the 1934 Reich Banking Law. Existing accounts have traced its origins to the 1931 banking crisis or the 1933 Nazi seizure of power. Yet, rather than the outcome of a single financial or political crisis, banking regulation was the product of longer-term discussions on national security, legal rationale, and financial globalization. Prior to World War I, officials expressed concerns over Germany's dependence on foreign capital, while later efforts to improve liquidity in the banking sector continued in the 1920s. The construction of a regulatory policy thus arose from a series of investigations into how to protect the German economy from foreign crises, thereby reflecting the interdependence of politics and finance.