alternatehistory.com

In a timeline where Germany united under Prussian leadership 1848, assuming its monarch takes the initiative, into a federal state similar to Wilhelmine Germany with its OTL borders + the Germanic areas of the AH empire, and barring any major demographic catastrophes or disruptions, what is Germany's potential population say, 200 years later, assuming OTL levels of prosperity (i.e. Germany isn't a low income, overcrowded country like Bangladesh or something)?

What about after a short war with Russia that results in the annexation of the Baltic States? By my calculations Germany today + Czech republic, Austria and the formerly-German territories of present day Poland amount to about 112 million. Adding in the Baltics is about 6 or so million more. So assuming no WWI or WWII, but also that fertility decline following industrialisation and rising living standards will be broadly similar to the general trend observed throughout most of the OTL developed and developing world, where would it realistically end up?
Top