Data for: The heavy plow and the agricultural revolution in Medieval Europe

Abstract of associated article: This research sheds new light on the much-debated link between agricultural productivity and development. We do so by estimating the causal impact of a large shock to agricultural productivity—the introduction of the heavy plow in the Middle Ages—on long run development. We build on the work of Lynn White, Jr. (1962), who argued that it was impossible to take proper advantage of the fertile clay soils of Northern Europe prior to the invention and widespread adoption of the heavy plow. We implement the test in a difference-in-difference set-up by exploiting regional variation in the presence of fertile clay soils. Using a high quality dataset for Denmark, we find that historical counties with relatively more fertile clay soil experienced higher urbanization after the heavy plow had its breakthrough, which was around AD 1000. We obtain a similar result, when we extend the test to European regions. Our findings substantiate that agricultural productivity can be an important driver of long-run development.

本研究对农业生产力与发展的争议性联系进行了新的探讨。我们通过估算对农业生产力的一次重大冲击——中世纪引入重型犁——对长期发展的因果影响，实现了这一目标。我们借鉴了林恩·怀特（Lynn White, Jr.）于1962年的研究成果，他提出，在重型犁的发明和广泛应用之前，人们无法充分利用北欧肥沃的粘土土壤。我们通过利用肥沃粘土土壤存在的区域差异，在差异-差异设置中实施这一测试。利用丹麦的高质量数据集，我们发现，在重型犁取得突破性进展的公元1000年之后，相对拥有更多肥沃粘土土壤的历史县经历了更高的城市化。当我们将测试扩展到欧洲地区时，也获得了类似的结果。我们的发现证实了农业生产力可以是长期发展的重要驱动力。