Modern Library Holdings and Historic Economic Growth

In a broad sample of cities, population growth robustly correlates with changes in the number of observed scholarly deaths. I document this fact using library data, argue it reflects structural links between intellectual and economic activity and develop a statistical framework to empirically exploit this relationship. Combining available city growth estimates with predicted growth from author counts improves existing data. More generally, author counts provide a disaggregated and high-frequency economic proxy that opens new avenues for research. I illustrate these opportunities in a data scarce environment by formally investigating the economic impact of the Mongol invasions on Iraqi cities for the first time.