The project aims to create an agrarian history database of tithes in Sweden for the period 1665 to about 1800. The database will contain harvest-dependent tithe volumes. Data will shed light on grain production and its variability in time and space. Our aim is to create a nationwide series of annual data over tithe on parish level. The practical work will consist of excerpting and analysis of the extensive tithe records. The precise investigation will vary between regions depending on the point of time at which fixed tithes were introduced. Geographical differences in this respect were considerable. Many counties and provinces had flexible tithes until around 1750, e.g. Halland, Medelpad, Närke, Västerbotten, Värmland and Södermanland. In some provinces, such as Scania and Dalecarlia, harvest-dependent tithes were practiced as late as in the 1800s. The planned database will be freely available and will have a wide range of applications. Harvest indicators are of interest in research areas such as climate, environment, history, economic history, human geography and archaeology. It must be stressed that the Swedish source material is in some respects unique, few other European countries have preserved a harvest indicating material of such temporal and geographic coverage. Therefore there is reason to believe that the database will generate interest in scientific environments also outside Sweden and stimulate ongoing and coming international research projects.