Most questions about the sources of agricultural growth during the ‘first agricultural revolution’ are still debated. For the Prussian province of Westphalia, we estimated a translog production function to determine the contribution of intensification and technical change from 1830 to 1880. Additionally, we present evidence on the impact that neutral and biased technical change had on growth. Furthermore, we examine whether spatial differences can be identified concerning the sources of agricultural growth and whether they followed a von Thuenen pattern around the demand centre of the rising industrial belt on the Ruhr River. In addition, we explain why, under the conditions of pre-industrial agriculture, regions with the highest output growth did not necessarily have to exhibit the most dynamic TFP-growth, even if they contributed, on average, the most to output growth.