I've been working on building a society for my story, but I've run into what I consider to be a significant problem. What are the different professions required to maintain a society of a technological level of ~1800? How much demand is there for these professions compared to each other? (Such as you need X amount of farmers as opposed to X amount of blacksmiths.)
Roughly, at around 1800, for a moderately fertile country such as England, you would need:
- 20% of the population in agriculture (farmers and their families).
- 25% of the population engaged in various manufacturing jobs or families of men engaged in manufacturing jobs (including blacksmiths, shoemakers, tailors, carpenters and also factory workers making thread, cloth, iron, bronze, machinery, glass etc.)
- 15% of the population in domestic service (if we include women servants; keeping house was hard work before washing machines, vacuum cleaners, microwave ovens and fast-food restaurants).
- 10% of the population engaged in commerce (retail shops were all the rage, there were very few large department shops and there were no nation-wide chains such as Wallmart or Carrefour).
- 5% day labourers (10% with their wives and children).
- 6% of the population would have independent financial means of be members of the families of financially independent men. Those are the people who engage in politics, run for members of parliament, pursue scientific research and so on.
- All other occupations and professions would be rare. There are very few civil servants, social workers, soldiers, sailors, lawyers, doctors etc.
For real numbers you cannot beat A Vision of Britain, which offers (among other delicious treats) synthetic tables extracted from the historical census returns. For example, for the 1841 census (numbers for England and Wales, occasionally rounded):
- 16.5% percent of the population were engaged in commerce, trade, and manufacture.
- 7.9% percent of the population were engaged in agriculture, of which:
- 20% were farmers and graziers.
- 76% were agricultural labourers.
- 4% were gardeners, nurserymen and florists.
- 4.2% were labourers.
- 0.3% were military (meaning land forces) and 0.6% were naval. If Scotland is included, those numers climb to 0.7% land forces and 1.2% naval.
- 0.3% were professional persons (that is, engaged in liberal professions, such as medical doctors, lawyers, professors, or architects).
- 0.8% were other educated persons following miscellaneous pursuits.
- 0.1% were engaged in government and civil service (the past is a very foreign country, isn't it).
- 0.1% were parochial, town, and church officers, including police and law-officers.
- 6.3% were domestic servants.
- 2.8% were independent (or as we would say today, rentiers, people who have sufficient independent income from property or investment).
- 1.1% were almspeople, pensioners, paupers, lunatics, and prisoners.
- In total, the preceding occupations represent 41% of the population, leaving a residue of 59% of population not engaged in an occupation (which corresponds nicely with about 50% of the population being children and married women).
Note that at that time England was the world's leading exporter of manufactured goods; England had also the world's largest merchant marine. In other countries the percentage of people engaged in making manufactured goods and in trade would be smaller or much smaller. In countries which were large exportes of agricultural products (such as Hungary or Wallachia) the percentage of people engaged in agriculture would be considerably higher.
In general, countries participate in international trade, and the occupations of their inhabitants depend not only on the level of development but also on what each country exports and imports; in the time frame of interest, England specialized in exporting manufactured goods, and imported staple foods, which means that the number of people engaged in industry was higher than the average developed country, and the number of people engaged in agriculture was lower. Socio-political structure and culture are also important.
1800 tech level is quite loose definition. It can be anything from hunting-gathering tribes in South-America to England in the early industrial revolution. I will chose the latter, and rely heavily on this link:
England's population was about 8 million at the time
36% of your people will still be farmers and their families.
Another 36% will be rural non-farmer.
This includes a lot of things: Priests, teachers, medics , blacksmiths and coopers and potters, traders, landed gentry, majors... I think one priest and medic per 100 people should be more than enough for the period. From craftsmen you will need somewhat higher density, but these numbers depend on the sizes of the avarage settlements. If the villages are small, you need more blacksmiths to get everybody's horses iron-shod. Same holds for majors and local judges.
And you need quite a lot of traders, to carry the products of the country into the cities, and then sell the goods of industry on the land.
The remaining 28% is the urban population.
You need one king and some royal family members.
You need some bishops and other high-ranked clerics.
You need some thousands soldiers and naval sailors.
Some thousands of officials for public administration: from ministers to country tax collectors.
Some thousand businessmen: bankers, merchants and factory owners.
Some thousands of engineers, and some hundreds of scientist and university professors.
Tens of thousands of lawyers and medics and priest and teachers again.
The remaining will be workers, sailors, craftsmen, tailors and hairdressers, shopkeepers, and the sinewies of those.
Policemen and criminals are also unavoidable.
Of course, one (a communist for example) can argue, whether bankers and factory owners and priests are actually needed, but I think, that to have a specific 1800 tech level, you need a quite similar society. (for example, with no capitalism, you probably won't get India-going sailing ships.)