when I read Road to Wigan Pier I realized that the 20th Century British term "middle class" had an almost unrecognizable meaning compared to what Americans think of as "middle class"
So the first thing you need to figure out, to answer the question "did the middle class exist back then" is: which cultural definition of middle class are we even using to begin with?
You don't need to answer that, in fact, I explicitly handwaved it away. The question is - is there a class between the elites and the serfs, and the answer is always yes. There are always people that the elites need in order to operate a successful polity, but those people are not part of the ruling class.
I’ve always heard that it was the class in between the upper class/nobility, and the working class. That is, the class that isn’t able to just indefinitely stop working and sustain itself by things they own. But also isn’t living paycheck-to-paycheck and forced to work. Professionals in lucrative careers and successful small business owners. This makes more sense to me that the sort of typical misapplication to people around median income in the US.
Around median income is already a thing we have a name for (we can call it median income), and it tells us approximately nothing about their position in terms of labor relations or social class.
Working class people should unionize, they should band together to prevent exploitation. Middle class people don’t have to worry about exploitation, they can walk if they want to. They should form guilds and professional societies, to keep unqualified pretenders out of their fields.
"Middle class" is super-poorly defined. Marxists use it to mean petit bourgeoisie (ie people who own capital, plus professionals, so right from the start you have an anomaly, in that, say, a doctor is middle class even if they don't own anything; it's not purely capitalists). As you say Americans tend to use it to mean 'practically everybody'. The British definition has always been complex and is at this point probably complex enough that it's impossible to fully pin down; a huge part of it is _self-identification_ (there are plenty of British millionaires who consider themselves working class).
I mean, I kinda get it, if you want to retire in the US you probably need a million dollars at least (although, not just in the bank, spread throughout retirement funds and real estate). So I could see a working class millionaire. Technically a retiree is living off their wealth, but IMO that’s an edge case.
"Middle class" is often used as a translation of "bourgeoisie" from "bourgeois" which literally means "town dweller" ie. a city dweller.[0] It also means "someone who belongs to neither the aristocratic, clerical, nor military classes."[0] This distinction was useful because the Three Estates system grouped both city dwellers and peasants into a single class (the third estate).[1] Similarly the English word "middle class" was at one point used by Marxists to describe non-aristocratic, non-working class urbanites and equated middle class directly with "bourgeoisie."[2] This class included factory owners who could be richer than the average noble. Our modern usage of "middle class" would never include factory owners, bankers etc. but this definition did.
You end up with something like this:
Old: Nobles -> "Middle class" -> Peasants
Marxist: -> Nobles -> "Middle class" -> Working Class
In both of these, "middle class" means "Not a noble. Could be a rich merchant"
Modern: Rich -> "Middle class" -> Working class
Here, "middle class" means "Middle income. Owns a house or an expensive apartment." "Working class" is the common term used here but also includes people that do not work.
>Around median income is already a thing we have a name for (we can call it median income),
Nobody uses this term. For example, nobody would say they are a "median income" family. Additionally, not all of what people today would consider "working class" work for other people, and cannot join a union. For example, street vendors often do not make much money[3] and it does not make much sense to categorize them as "middle class" because they are not being exploited by their employer (as they have no employer). Unions exist for highly skilled jobs as well, such as air traffic controllers, which make $137,380 per year on average.[4][5] Defining "middle class" as someone who "doesn't need a union" (taking how to qualify that as given) also leaves open the question of what the "upper class" means in that scenario, being that we are not using income as the barometer for class in favor of union status. Would the street vendor be "upper class" if he had a worker? If anything, I would say we already have a term for what you are essentially describing: "unskilled labor." Unskilled laborers need unions more than skilled ones. This is a direct effect of unskilled laborers making less money due to lack of a marketable skill.
>it tells us approximately nothing about their position in terms of labor relations or social class.
It actually tells us a great deal about social class. People of similar incomes will live in their own neighborhood whether or not they have that money from being in a union or from a non union job (leaving the definition of that aside). It is all decided by income level. Living in a middle class suburb is a vastly different experience from living in an apartment in a poor neighborhood in the city.
Lastly, the "right" definition is not really important as much as explaining what you mean by that word when you use it. In the context of history, as in this article, the definition definitely matters.
So the first thing you need to figure out, to answer the question "did the middle class exist back then" is: which cultural definition of middle class are we even using to begin with?