The writers take on the hypothesis of Lynn White Jr that the heavy plough led to an increase in population and urbanization. The team of researchers are Thomas Barnebeck Andersen, Peter S. Jensen and Christian Volmar Skovsgaard from the Department of Business and Economics at the University of Southern Denmark.
You can download the full paper after the abstract.
The Heavy Plough and the Agricultural Revolution in Medieval Europe
This research tests the long-standing hypothesis put forth by Lynn White, Jr. (1962) that the adoption of the heavy plough in Northern Europe led to increased population density and urbanization. White argued that it was impossible to take proper advantage of the fertile clay soils of Northern Europe before the invention and widespread adoption of the heavy plough. We implement the test in a difference-in-difference set-up by exploiting regional variation in the presence of fertile clay soils across European regions as well as across Danish historical counties. Consistent with the hypothesis, we find that regions with relatively more fertile clay soil experienced higher urbanization and population growth after the heavy plough had its breakthrough, which was approximately around the closing of the first millennium AD. Our findings suggest that the heavy plough accounts for around 10% of the increase in urbanization and population density during the High Middle Ages.
Andersen, Thomas Barnebeck and Jensen, Peter S. and Skovsgaard, Christian Volmar, The Heavy Plough and the Agricultural Revolution in Medieval Europe (December 3, 2013). Discussion Papers on Business and Economics, University of Southern Denmark, 6/2013. Available at SSRN: http://ssrn.com/abstract=2362894 or http://dx.doi.org/10.2139/ssrn.2362894