The concept of socio-ecological transitions is used to analyse the quantitative importance of physical imports and exports for the Habsburg Empire and the United Kingdom in the 19th and early 20th centuries. For the Habsburg Empire, a new dataset of foreign trade and social metabolism is presented. For the United Kingdom, the analysis relies on previously published data. Foreign trade volumes increased in both countries in the long run. Total trade volumes were much higher in the United Kingdom throughout the entire time period, on average by around a factor four. Physical factors explaining the disparities in structure and volume of foreign trade in the two countries are differences in (1) the temporal patterns of the socio-ecological transition and (2) domestic resource endowments. In both countries, energy carrying materials, i.e. fossil fuels and biomass, were the dominant resources in physical foreign trade. The analysis focuses on the physically most important material groups: coal, wood and cereals, and discusses the role of imports and exports in relation to domestic resource provision and environmental pressures. Physical foreign trade increased at a faster pace than domestic resource extraction and consumption. The socio-ecological transition was thus accompanied by rising international integration of resource supply.