In a rather large broad brush view of history, we end up with the following key things for the pre-industrial world:
Malthusian constraints apply;
Agriculture swallowed up the majority of the population and generated the majority of the states revenue (in most cases);
Economic growth for a significant period must have been near to 0 since the birth of Christ, if it had been a tepid 0.5% every year from 0 to 2000 (assuming that the year 0 had a per capita average of $400 Geary-Khamis dollars) the end result would have been a per capita GDP of some $8.6 Geary-Khamis dollars. So it was near enough to 0 to be unnoticeable to most people during the course of their lives. Even the most optimistic projections of growth from 0 to 1000 notes a mere doubling or a tripling of per capita GDP (and even then that’s generous) so a 1000 years granting a mere doubling or tripling of wealth per person on average. In comparison in the 172 years after 1820 per capita GDP in the UK grew tenfold while in the US it grew twentyfold;
Population over the first two million years of human history did not exceed 0.0001% per year, around 10,000 years ago with the advent of agriculture it rose to a clipping 0.036% per year, come the first century AD it was now barrelling along at a clipping 0.056%, passing to 0.5% around 1750, and finally 1% at the start of the 19 century.
Growth was driven either by, institutions (generally property rights, scientific rationalism, capital markets, which form the foundations for innovation and incentives etc), however blithely assuming that the economy of a pre-industrial nation must grow is rather irresponsible.
The first point is precisely why economics is called the Dismal Science. From Malthus himself, Second Edition of An Essay on the Principle of Population
"A man who is born into a world already possessed, if he cannot get subsistence from his parents on whom he has a just demand, and if the society do not want his labour, has no claim of right to the smallest portion of food, and, in fact, has no business to be where he is. At nature's mighty feast there is no vacant cover for him. She tells him to be gone, and will quickly execute her own orders, if he does not work upon the compassion of some of her guests. If these guests get up and make room for him, other intruders immediately appear demanding the same favour. The report of a provision for all that come, fills the hall with numerous claimants. The order and harmony of the feast is disturbed, the plenty that before reigned is changed into scarcity; and the happiness of the guests is destroyed by the spectacle of misery and dependence in every part of the hall, and by the clamorous importunity of those, who are justly enraged at not finding the provision which they had been taught to expect. The guests learn too late their error, in counter-acting those strict orders to all intruders, issued by the great mistress of the feast, who, wishing that all guests should have plenty, and knowing she could not provide for unlimited numbers, humanely refused to admit fresh comers when her table was already full."
To sum it up; that is the hell on earth of Malthus we have the following snippets; (borrowed from A Farewell to Alms)
Before 1800 income per person – the food, clothing, heat, light and housing available per head – varied across societies and epochs. But there was no upwards trend. A simple but power mechanism… the Malthusian trap, ensured that short term gains in income through technological advances were inevitably lost through population growth.
Thus the average person in the world of 1800 was no better off than the average person 100,000BC. Indeed in 1800 the bulk of the world’s population was poorer than their remote ancestors. The lucky denizens of wealthy societies such as eighteenth-century England or the Netherlands managed a lifestyle equivalent to the Stone Age… but the vast swath of humanity in East and South East Asia… eked out a living under conditions probably significantly poorer than those of cavemen.
The quality of life also failed to improve on any other observable dimension. Life expectancy was no higher in 1800 than for hunter gathers: thirty to thirty-five years. Stature a measure both of the quality of diet and of children’s diet and exposure… did not improve significantly.
While some might be screaming something to the effect of “No way!” Its instructive to remember that while there might be swings up in living conditions, and in wealth in a long view these were just “noise” in the figures and really represent no real upwards trend. As soon as living conditions and wealth rose, they pretty soon fell back.
The vast majority of human societies, from the original foragers of the African savannah through settled agrarian societies until about 1800, led an economic life shaped and governed by one simple fact: in the long run births had to equal deaths… The Malthusian model supplies the mechanism to explain this long run population stability. In the simplest form there are just three assumptions.
1. Each societies has a birth rate, determined by customs regulating fertility, but increasing with material living standards,
2. The death rate in each society declines as living standards increase,
3. Material living standards decline as population increase.
In a stationary population birth rates equal death rates.
Basically the graph to explain the Malthusian model is rather simple.
The horizontal axis for both panels is material income, the amount of goods and services available to each person. In the top panel birth and death rates are plotted on the vertical axis. The material income at which birth equal death rates is called the subsistence income, indicated in the figure by y*. This is the income that just allows the population to reproduce itself. At material incomes above this the birth rate exceeds the death rate and population is growing. At material rates below this the death rate exceeds the birth rate and population declines. The subsistence income is determined without any reference to the production technology of the society. It depends only on the factors that determine the birth rate and those that determine the death rate. Once we know these we can determine the subsistence income and life expectancy at birth. In the bottom panel population is shown on the vertical axis, once we know population, that determines income and in turn the birth rate and death rates.
With just these assumptions it is easy to that the economy will always move in the long run to the level of real incomes at which birth rates equal death rates. Suppose population starts at an arbitrary initial population, No in the diagram. This will imply an initial income y0. Since yo exceeds the subsistence income, births exceed deaths and population grows. As it grows, income declines. As long as the income exceeds the subsistence level population growth will continue, and incomes will continue to fall. Only when the income has fallen to the subsistence level will population growth cease at the equilibrium level, N*, and the population stabilize.
Suppose that instead the initial population had been so large the income was below subsistence. Then deaths would exceed births and population would fall. This would push up incomes. The process would continue until income was again at subsistence level. Thus whenever population starts from in this society it always ends up at N*, with income at subsistence.
So why are there these assumptions?
The justification for the decline in material incomes with higher populations is as follows. Any production system employs a variety of inputs, the principal ones being land, labour, and capital. The law of diminishing returns holds that, if one of the inputs to production is fixed, then employing more of any of the other inputs to production will increase output but by progressively small increments. That is, the output per unit of the other input factors will decline as their use in production is expanded, as long as one input factor remains fixed.
In the preindustrial era land was the key production factor that was inherently fixed in supply. This limited supply implied that average output per worker would fall as the labour supply increased in any society, as long as the technology of that society remained unchanged. Consequently average material income per person fell with population growth.
Consider a peasant farmer with 50 acres of land. If he alone cultivates the land then he will maximize output by using low intensity cultivation methods: keeping cattle or sheep which are left to fend for themselves and periodically killed for meat and hides. With the labour of an additional person milk cows could also be kept, increasing total output. With yet more labour the property could be cultivated as arable land with grain crops. With even more people the land could be cultivated more intensely as garden land. Add 500 people and you will hit a wall, some of them will do nothing because there is no work they can do.
So what does this mean for Pre-Industrial NESing? It means in very simple terms that in all but the rarest cases; most of your income derives from agricultural sources. It also means that any increase in population all things held equal will decrease the wealth in aggregate of individuals. It also means that the more people you have the more fragile your economy is, assume for a moment that you have a drought with a low population people will flow to the areas where it is not so dry, with a large population that land will likely already be under cultivation and people will starve. It also means that your incomes are subject to the vagaries of changing seasons, to a large degree, if there is a crop failure the major source of your income has just collapsed. There is some degree of difference in the likely effects, some states have no sliding scale system, so even if there is a crop failure the people are still obliged to hand over the same amount of goods or payment, that is a quick way to head into feudalism, over a long period more and more people will inevitably fall into debt no matter how careful they are. With a sliding scale system you become subject to the seasons, if there is a crop failure your troops are likely to go hungry, if there is a bounty you gain a proportional increase.