The HANZE dataset covers riverine, pluvial, coastal and compound floods that have occurred in 42 European countries between 1870 and 2020. The data was collected by extensive data-collection from more than 800 sources ranging from news reports through government databases to scientific papers. The dataset includes 2519 events characterized by at least one impact statistic: area inundated, fatalities, persons affected or economic loss. Economic losses are presented both in the original currencies and price levels as well as inflation and exchange-rate adjusted to 2020 value of the euro. The spatial footprint of affected areas is consistently recorded using more than 1400 subnational units corresponding, with minor exceptions, to the European Union’s Nomenclature of Territorial Units for Statistics (NUTS), level 3. Daily start and end dates, information on causes of the event, notes on data quality issues or associated non-flood impacts, and full bibliography of each record supplement the dataset. Apart from the possibility to download the data, the database can be viewed, filtered and visualized online: https://naturalhazards.eu. The dataset is designed to be complimentary to HANZE-Exposure, a high-resolution model of historical exposure changes (such as population and asset value), and be easily usable in statistical and spatial analyses. The dataset contains the following files (CSV comma-delimited, UTF8, and ESRI shapefiles in zipped folders) HANZE flood events database HANZE_events.csv - Flood event data HANZE_references.csv - List of all references HANZE_events_regions_2010.zip - Flood event data as GIS file (regions v2010) HANZE_events_regions_2021.zip - Flood event data as GIS file (regions v2021) Supplementary data Table_S1_countries.csv - Country codes/names Table_S2_regions_v2010.csv - Region codes/names, v2010 Table_S3_regions_v2021.csv - Region codes/names, v2021 Table_S4_currencies.csv - Data on all currencies used in the study area since 1870 Table_S5_conversion.csv - Conversion rates applied to compute losses in 2020 euros Table_S6_deflators.csv - Gross domestic product deflator by country, 1870-2020 Table_S7_deleted_events.csv - Flood events in HANZE v1, which were excluded from v2 Regions_v2010_simplified.zip - Region map, v2010 Regions_v2021_simplified.zip - Region map, v2021

This work was supported by the German Research Foundation (DFG) through project "Decomposition of flood losses by environmental and economic drivers" (FloodDrivers), project no. 449175973