War, Coal, and Forced Labor: Assessing the Impact of Prisoner-of-War Employment on Coal Mine Productivity in World War I Germany

This paper assesses the causal relationship between POW assignments and labor productivity for a vital sector of the German World War I economy, namely coal mining. Prisoners of war (POWs) provided significant labor. Combining data on all Ruhr mines with a treatment-effects approach, I find that POW employment alone accounted for 36% of the average POW-employing mine’s annual productivity decline over wartime. Estimates also suggest that the representative POW’s productivity averaged 32% of the representative regular miner’s productivity, and that POWs’ contribution to wartime coal output amounted to 3.9%. Violence did not serve as a powerful work incentive. The deposited files include a stata-file containing the data, a word-file containing the stata-code needed to replicate the results shown in the paper, and an excel-file containing the data on two figures.