How populous is the Gift?

[Nihlus]

In the far North of Westeros, the Night's Watch presides over a strip of land, which they protect from the wildlings in exchange for the villages and towns in that land creating the resources (mainly food) that sustain the Watch. This land is essentially its own independent state, a tenth region or an eighth kingdom. But "strip" is understating things; the Gift is said to be a rectangle extending 300 miles from east to west and 150 miles from north to south. That's a surface area of 45,000 square miles. Nearly the size of all of England (50,300 square miles).

My question is this: how many people actually live there? What even is the minimum number of people that need to live there to sustain between 1,000 and 10,000 soldiers not producing their own food? I ask because even the most low-balled estimates of its size would give the Gift a population of around half a million (population density similar to medieval Scotland, which seems conservative given it's describe as "good farmland"). But I can't recall anything supporting there being that many people- certainly it doesn't seem like there's thousands of villages scattered across the Gift when people are traveling through it, nor are there any major towns of note besides Mole Town.

What say you?

[Free Northman Reborn]

A good comparison for the Gift's carrying capacity would be the known lands close to it. The Umbers, Karstarks and Mountain Clan lands.

The Umber numbers are unknown, but both the Karstarks and Mountain Clans have been shown to be able to raise in the region of 3000 soldiers. Using the 1% rule, or even a less realistic 2% rule, would give the Karstarks between 150k- 300k people. More or less the same for the Mountain Clans. The Umbers are presumably in a similar category. 

So in ancient times, that was probably the population of the Gift. Before the Targaryens took it from the Starks and gave it to the Watch. Today it is largely abandoned, as explained by Bran when he travels through the area with Meera and Jojen.

[falcotron]

In ASoS Jon V, we're told that Brandon's GIft used to be farmed but is now mostly empty. There's Mole's Town, of course, which is "bigger than it seems", but it's still just a small town, and there don't seem to be any other remaining settlements mentioned.

That's presumably why Jaehaerys gave them the New Gift—but, according to WoIaF:

Quote

It may be that the Starks feared that, under the control of the Castle Black, the New Gift would inevitably decline—for the Night’s Watch would always look northward and never give much thought to their new tenants to the south. And as it happens, that soon came to pass, and the New Gift is now said to be largely unpopulated thanks to the decline of the Watch and the rising toll taken by raiders from beyond the Wall.

We're told that there are a few villages and many holdfasts in the New Gift, but when Bran and company stop in Queenscrown, which was supposed to be one of the biggest holdfasts, it's abandoned.

I think we're also told that the Norrey mountain clan pays little attention to the borders of the Gift so presumably they grow some food there, but presumably they also don't donate it to the Watch.

The rough number that I learned is 20 adults per fighting man in non-urban medieval territories. I know Ran used 100:1 for some of his calculations. A quick search shows that it can be anywhere from 4:1 to 40:1 depending on a wide range of factors. Here, none of the farmers double as fighting men, and there isn't a great transport infrastructure, and the land is livable but probably not exactly bountiful, so let's err toward the high end and say it takes 35,000 farmers to support the 1,000 men of the Watch.

And then, since we're explicitly told the Watch neglect their duties managing it, let's say they're only taxing a fifth of the villages they could be, so say 175,000 population.

Even if we assume only a quarter of the Gift has most of the population (it's only the eastern half that's said to be arable fields, and the northern half has been abandoned for centuries while the southern half was part of the North until pretty recently), that actually would probably look "largely unpopulated".

And maybe it's not that implausible. If you've got no lords to keep you where you are, and you can go south to Umber lands and be protected from Wildling raids, how long would you stay in the Gift?

[Nihlus]

18 minutes ago, Free Northman Reborn said:

A good comparison for the Gift's carrying capacity would be the known lands close to it. The Umbers, Karstarks and Mountain Clan lands.

The Umber numbers are unknown, but both the Karstarks and Mountain Clans have been shown to be able to raise in the region of 3000 soldiers. Using the 1% rule, or even a less realistic 2% rule, would give the Karstarks between 150k- 300k people. More or less the same for the Mountain Clans. The Umbers are presumably in a similar category. 

So in ancient times, that was probably the population of the Gift. Before the Targaryens took it from the Starks and gave it to the Watch. Today it is largely abandoned, as explained by Bran when he travels through the area with Meera and Jojen.

Where does the 1% rule come from again? It definitely fits the many, many accounts of medieval armies and mustered I've seen compared to demographic studies, but what source is that specific percentage drawn from?

[Free Northman Reborn]

I don't have the primary source, but Ran has done some reading on it and used it as a basis for his population estimates for Westeros as a whole. My interpretation of it is that it is the percentage of the total population that a typical medieval society can raise to arms and support logistically in the field for a reasonable amount of time.

So it is not the number of able bodied men you can gather together at a central point for a quick brawl. It is the number of men you can support in the field, and project into the theatre of war. Now consider that the Karstarks did so over a distance of maybe 500 miles just to get to Winterfell. Marched their 2300 men over rugged terrain, fed them, fed their horses and beasts of burden, provided them with weapons and armor and did so over a period of months. Imagine the supply train necessary to achieve that.

And they did it again when they sent men to join Rodrik's army, and again when they send 450 men with Arnolf Karstark to the Wolfswood.

This means that you aren't talking about every able bodied man you can find, but about the very small percentage of your population that you can logisticaly support in the field, and project beyond your own borders for a sustained period of time. The constraint is therefore economic, and not demographic in nature.

EDIT

Now consider that at its height the Watch had 10,000 men. And back then they only had Brandon's Gift. Now we can imagine that the support and donations from other lords would have been greater in those days, and we can imagine, based on today's ratio, that maybe a third of the 10,000 were stewards and therefore involved in the farming activities throughout Brandon's Gift. But that still requires a major population in Brandon's Gift, to support such a large military organization.