The first version of the data was constructed by a team of researchers based on national historical statistics: Marc Badia-Miró, Erik Buyst, Kerstin Enflo, Emanuele Felice, Frank Geary, Jordi Guilera, Kari Anne Janisse, Peter Sandholt Jensen, Herman de Jong, Martin Henning, Alexander Klein, Julio Martínez-Galarraga, Jørgen Modalsli, Cristina Victoria Radu, Joan Ramon Rosés, Teresa Sanchis, Lennart Schön, Max-Stephan Schulze, Paul Richard Sharp, Tom Stark, Dirk Stelde, Daniel A. Tirado, Ulrich Woitek, Nikolaus Wolf, and Gabriela Wüthrich.
The new version 6 (2020) includes several updates and corrections, an extension of the data to 2015 and regional GDP data in 2011 PPP.
For a description of the data and an extensive documentation of sources see Joan R. Rosés and Nikolaus Wolf (eds), The Economic Development of Europe's Regions A Quantitative History since 1900, Routledge 2018.
For the basic methodology and a discussion of general patterns in the data see Joan R. Rosés and Nikolaus Wolf (2018), "Regional Economic Development in Europe, 1900-2010: a description of the Patterns", CEPR DP 12749.
Update (version 6): Rosés and Nikolaus Wolf (2021), "Regional growth and inequality in the long-run: Europe, 1900–2015", Oxford Review of Economic Policy, Vol. 37, No. 1, 2021, pp. 17–48.
Country Chapters, country-specific data, US state-level data
The book contains additional regional data on individual European countries, in several cases reaching back before 1900 and including data for smaller geographical units such as NUTS 3. The book also contains new estimates of nominal GDP for US states, 1880 - 2010 by Alex Klein.
For individual country chapters, see here.
When using these data, please make the following reference: Rosés-Wolf database, version 6 (2020).