You make some rather big assumptions here.
- That they could just reclaim all the land that is now free thanks to dead people and that it is any easier to reclaim that other land around that wasn´t settled before
- That they ever stop raiding each other (its an easy way for them to get stuff also glory etc.)
- That there is going to be one tribe that comes out of is on top of the other instead of many small tribes that raid each other all the time.
- That the plague will burn itself out completly and won´t stay around like some did rl and just keeps killing.
- That they are able to just jump back form losing 50+% of their total pop.
- hello extremly high pop. growth while the pressure that keeps it at ~5% or less per 100 years is still there
- That they will be able to get more food per person now then they did before and are able to use that to fuel the pop. growth
It is here that being a stone age civ comes to bite them as they don´t have any of the tool, knowledge or infracture that would allow for a fast bounce back from ~50% lose of total pop.
This doesn´t include what happens when "outside" force start to settle into the lowlands.
1) Previously cultivated land is extremely easy to reclaim compared to wilderness. This is doubly true for stone tools, because theres a massive difference between taking over already cleared land, with extremely rich forage and hunting due to crops and animals gone feral in the empty period
2) Raiding is the harder way to get stuff in the aftermath of a plague, it has high risks of reinfection, and also the people you'd normally raid are dead. You have empty farms instead.
3) Whoever manages to grab the most unclaimed land under one administration is going to have a massive advantage in manpower over other parties. The plague had reset tribal boundaries, and the pre-cleared land allows one tribe to grab a lot of territory before their tribal identity fades with time, like it would for the original Lowlands setting.
4) Plagues burn out in the stone age. This is simple fact because small populations mean that any plague with high lethality would rapidly kill any population that
5) This is also historical fact. Most of the pressures against population growth are:
5.1) Food and water shortage. Not an issue due to pre-cleared farmland.
5.2) Population density induced diseases. Not an issue. Density is basically at the minimum.
5.3) Difficulty of converting wilderness to usable land. Not an issue, the new settlers have to tear up bushes instead of old growth high density forest, wells need only to be cleared, not dug from scratch and construction materials are piled up in convenient former homes.
5.4) Conflict between residents and new population migration. How nice that theres no residents.
Population growth has only very rarely been limited by the ability to pop out babies. Theres a lot of nomadic tribes who would settle if only they could find easy to cultivate land which aren't already claimed. Due to the previous Lowland situation they didn't even have many techs to lose which might limit productivity.
And it turns out that Malbyn is still alive this turn. Not Cadnys mind you. She died of old age.
Now that I have done the Epic Age rolls for the Great Bay area.
The Arthwyd have two Martial Heroes.
The Merntir have a Martial Hero and a Tech Hero.
The Nomads have a Genius Martial/Heroic Diplo leading a horde against the Merntir.
This will be the stuff of gods.
It works with nomads when they have been united by a great leader. Pay them off until their leader dies and then wait for his horde to scatter and deal with those that remain to demand more tribute.
In fact, any nomad horde which demands tribute SHOULD be indulged where possible. Nomads don't like dying any more than anyone would, and if they could get loot without fighting any hordemaster would love to. It lets them save manpower for raiding civs who aren't reasonable.
Contrary to what it seems, a nomad tribe has a very strict population limit. The only thing is that they can achieve 50% mobilization compared to settled civilizations which can achieve 5% mobilization without crashing their economy.
I just don't want to be seen as a cash cow the best way to get rid of them in the long term is to make the fight not worth it
Good grief. It doesn't work. Nomadic tribes have very poor institutional memory, and this is speaking from the perspective of a settled civilization which has trouble remembering more than 3 generations worth of stuff. Nomads move, so they're always strangers each time, no reputation based defense would work because its always the first encounter.
No, he knows about you. The Nomads might have only met the Merntir, but they also know of the Arthwyd as the Merntir told them about them. As of such, the Nomad Genius knows that you exist and are like the Merntir, but that is about all he knows of you. He does expect you to send fighters to help the Merntir.
Noting that nomad hordes don't form for no reason. They SEEM nonsensical to outsiders, but its probably last turn's drought that triggered this horde. Loss of forage means the tribes unite and form up to try to get resources from a settled civ, if they're going to lose people anyway they'd rather lose people to trying to save some than to starvation.
It's not like they'll all attack as one massive horde under direct control of the Khan every time. There will be groups, divisions, parties led by the Khan's subordinates attacking other targets. Nomads or not, they're unlikely to win against one of our Heroes.
Note that nomad hordes very rarely attack in one huge combined mass. They'd strip the land bare and start starving within weeks if they did that.
Think less giant wall of warriors and more like "Theres 100 groups of 20 guys attacking 100 different places at once"