The project aimed to improve the European background database used by the Coordination Centre for Effects (CCE) to calculate ⁠Critical Loads⁠ (CLs) for eutrophication and acidification for (semi-) natural European terrestrial ecosystems. The database is used when member countries do not provide their own CL data to the CCE. In this case, the missing country data are replaced by the results of the background database when the CCE produces European CL maps. This report describes the (a) underlying datasets; (b) derivation of the input data for the CL model; (c) R packages and scripts developed; and (c) verification of the results. These results feed into international and national policy advice, e.g., they are an important input to the Gothenburg Protocol Review currently underway in the year 2021.