This dataset contains data from the sources 'Kervenregister' and 'Volkstelling' of Leiden in 1581. The dataset combines data on affluent tax payers ('Kervenregister') and demographic data on the inhabitants (census registers). One file concerns the data from the 'Kervenregister'. Four files concern information from the census register on four districts of Leiden (Burchstreng, Kerkvierendeel, Gansoord and Nicolaasgracht). Two other files contain data on widows and widowers mentioned in the two sources. These two files are documented as one file. Data has been collected by two students during a project in the postgraduate course 'Historical Information Processing' of Leiden University.