This map shows the percentage of the population aged 0-17 years. In order to be able to identify differences within countries, the map shows the differences at a regional level.
Source: Eurostat
Are you surprised how many or how few children there are in a region in Europe?
Interesting, in my part of Europe this coincides with developing and dynamic regions (a lot of employment, culture and progress).
Wonder if movement or birth rates affect the percentage the most?
Perhaps both. Maybe people are both more likely to move to AND have children in areas they feel more physically and economically secure.