Realistic vs. Fantasy Populations

[jwbjerk]

However, the problem is that for my fantasy setting, these numbers SEEM very large, even considering the rough equal land mass. But, how do I reconcile a large population of humans, or huminoids with areas that should also be populated with Dragons and other monsters ready to EAT and or other dispicible things to them. The sources I have for my games put cities (the largest unit save unique locals) at around 25,000 per, but how packed should these cities be to each other?

Remember that in the medieval world the vast majority of people were food producers (farmers, fishermen, etc.) and didn't live in cities. Today a single farmer can feed hundreds or thousands but with medieval methods the ratio is more like 1 to 1 (depending on the period, fertility of the area, and who you believe, etc)
You get a much thinner, evening distributed population than we have now.
For spacing your cities the primary consideration is food. There needs to be enough fertile countryside around them to support enough farmers to feed the city. A starving city doesn't grow.

In short: For those who care about these types of things - would it seem more believable to lean towards more historical accurate populations sizes, and if not, how much should they be reduced to be believable within a fantasy setting?

There were always wild relatively uninhabited lands in the real world. That's where the monsters are generally imagined to go, but in the real world there was usually a more prosaic reason for the uninhabited status, lousy soil, lack of reliable water, etc.

To figure out how this effects human(oid) populations, you need to figure out the balance of power between civilization and monsters. Are the monsters relegated to the outskirst, land that humans really wouldn't do much with anyway, or are the monsters pushing back, and occupying good land that humans would love to use if they could? A single dragon (depending on exactly what your dragons are like) could reasonably "ruin" hundreds of square miles for human habitation.

For a quick and dirty method i'd figure a percentage of human-useable monster dominated lands. If it was 50%, cut the humanoid population by 50%, i.e. to 10 million.