The persistence literature in economics and related disciplines connects recent outcomes to events long ago. Although this influential literature is promising, it raises serious questions about how to distinguish deep causal factors that persist across time from alternative explanations derived from the rapidly changing historical context or misuse of historical sources. We discuss two prominent examples that ground the rise of the Nazi Party in distant historical roots. Several econometric, analytical, and historical errors undermine the papers’ contention that deeply rooted culture and social capital fuelled the Nazi rise. The general lesson for persistence studies is that beyond careful econometrics and serious consideration of underlying mechanisms (including formal theory), they must pay scrupulous attention to the historical context and the limitations of historical data.