Maxperson
Morkus from Orkus
Not guard. Militia. A lot of able bodied men were given a minimum amount of training so that during wartime or an emergency, they could be called up to fight. These are not the guards you mention, but additional men that are proficient in a few weapons. They generally also had low morale, since they were not drilled constantly to fight and not run like soldiers and guards were.From what I was able to find on various message boards, the best argument I found on your end of the spectrum was, "the percentage of people in an army is roughly 5%, and increases up to a maximum of 10% during wartime. This means in a town of 1000, not currently fighting any wars, there should be approximately 50 trained guards. "
I then also saw, "The statistic is, in a medieval society, you're looking at about 90% of the population being subsistence farmers. 5% of the population being full-time military would mean that every other non-farmer is a guard. Remember that a town of 1000 people is actually not very big at all, and in an age where taxation is woefully unreliable, the government is fairly small. You'd be lucky to get 5 guards."
I also saw that the trained folk of a town would often be out of town on patrol, so many wouldn't even be in town ready to battle a dragon suddenly swooping in for an attack on the town.
So the estimate seems to range from 5 to 50 for a town of 1000. They're not beating an adult Red Dragon.
Your claim of 30% of the population being trained for warfare matches just one country: modern north Korea. That's it. No other nations were listed (old or modern) with such a high trained population level. Though nobody has good stats on, for example, Sparta.
I saw numbers that some cities trained every able bodied man like that, so you'd see 10-20% of the population able to be called up in an emergency. So going to that town of 1000, there would be 50-100 guards and another 100-200 militia. That's IF it were one of the hardcore towns that trained EVERY able bodied man for the militia. Many towns did not do that.