Acknowledgements
We are grateful to the Max Planck Institute for Demographic Research (MPIDR) and the Scientific Research Network Historical Demography (Research Foundation Flanders, FWO) for financing the meetings of the Urban demography network in Rostock (Germany) and Leuven (Belgium), which paved the way for this special section. Moreover, we would like to thank Siegfried Gruber (Max Planck Institute for Demographic Research, Rostock), Jan Kok (Radboud University Nijmegen/KU Leuven), Koen Matthijs (KU Leuven), Andrejs Plakans (Iowa State University) and Mikolaj Szołtysek (Max Planck Institute for Demographic Research, Rostock) for their useful comments and suggestions. Last but not least, a word of thanks goes to Robyn Donrovich (KU Leuven) for the language editing.
Notes
1. According to Le Play moral decay was a result of the advent of unstable families, as religion and tradition in patriarchal families had been handed down from one generation to the next, from father to son. The dethronement of the head of the household had led to a situation in which religion and tradition were no longer passed down the line as families broke up.
2. Ideas which were later further elaborated by Parsons (Citation1963).
3. In the case of Japan, the existence of stem families was already known for a long time.
4. http://www.ipums.org/
5. https://www.nappdata.org/napp/
6. http://195.37.34.109/cgi-bin/index.plx
7. http://www.ehps-net.eu/