Italy was also very populous, easily having over 10 million inhabitants in 1500. It is more impressive when we consider that Italy is geographically smaller than France and Germany, and also more mountainous. If Italy does not stagnate economically after the 16th century, it is very likely that its population will grow faster than OTL, although I think it would grow slower than Germany and France.France has always had a super large population: in 1328 the country had some 13 million people, and by 1500 it had 16 million. It was the most populous country in Europe even into the 18th century, having more people than Russia.
Germany as a whole had maybe a bit more than France—23 million in 1500 and anywhere from 27-34 million in 1600, though obviously it was much less centralized. With the imperial reforms being pushed through in Anno, it makes the empire a formidable rival for France.
In 1820, the states that would make up the future German Empire had 22 million inhabitants, while Italy had 20 million.
Another nation that grew little demographically was Spain, which had the same population as Great Britain in 1700 (around 8.5 million) and in 1820 it had 12 million compared to Great Britain's 20 million.
List of countries by population in 1700 - Wikipedia
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