War and democratization in the “long 19th century”: Introducing the Historical Varieties of Democracy Dataset

This article introduces the Historical Varieties of Democracy Dataset (Historical V-Dem), a comprehensive and unique dataset containing about 300 indicators, both de facto and more evaluative, describing various aspects of political regimes and state institutions. The dataset covers 85 polities globally – including most large, sovereign states, as well as some semi-sovereign entities and large colonies – and most time series extend from 1789 to 1920. The majority of indicators are from the Varieties of Democracy dataset, which already covers the period from 1900 to the present – and together they thus cover the bulk of “modern history”. But, Historical V-Dem also includes several new indicators for features that were particularly pertinent for 19th century polities. After having described the data, and the different strategies employed in Historical V-Dem to cope with methodological issues of reliability, validity, and cross-country comparability, we illustrate the potential uses of the dataset. We do so, first, by providing a descriptive account of patterns of democratization in the “long 19th century”. Second, we perform an empirical investigation of how inter-state wars affected patterns of democratization during this early part of modern history.