Although the present day is still plagued with inequalities and social injustices (and we need say no more about them), the average quality of life has improved gradually throughout history. Even the very poor in the present world are usually better off than peasants a few hundred years ago, and enjoy vastly better resources and life expectancy than primitive hunter-gatherers. And while there are still rich people with much better access to quality goods and comfortable lifestyles, the overall discrepancy has been decreasing over time.
Writers of speculative fiction often suppose that in the distant future, this trend will continue, and imagine utopian societies of ultimate equality where everyone has unlimited access to at least their basic needs. But what if something went wrong? What if the ruling class hoarded the best goods for themselves, leaving the rest of civilization in a state more reminiscent of the dark ages? Whether because of Fantastic Racism, obstructive social policies, or just overblown greed, a high-class elite lives in sumptuous luxury, while everyone else scrapes through abject poverty, with a minimal or nonexistent middle class between them. This can happen either in futuristic settings for fantastical ones, where it's likely tied to The Magocracy, with magic-users enjoying the fruits of their abilities and denying them to others. Either way, the crux is that society has the means to provide for everyone, but fails or refuses to do so.
Cities are naturally arranged by Urban Segregation, and not uncommonly become a Layered Metropolis, the rich on top and poor below. In extreme cases, the elite will be of a different race or species, regarding themselves as superior and may even sequester themselves on a floating city or continent, the better to separate themselves from the rest.
In such a setting, the protagonists will almost certainly be members of the lower class striving to redress the imbalance, probably by leading a revolution against the elites. If they succeed, in a cynical work they may find themselves occupying the high position, while the system of inequality endures. If any good elites are shown, they'll be a Defector from Decadence also trying to improve matters.
No Real Life examples, please.
- Kiddy Grade: In the future, the rich (who call themselves "Nobles"; with their ability to purchase entire planets to live on) literally treat those humans who are not as rich as a sub-species; going to such measures as wearing environmental suits so they won't breathe the same air as the poor (an issue which is mentioned in the series has led to the Nobles to have weaker immune systems); make indentured servitude to the Nobles' companies a standard of life on many planets and try to fund a terrorist conspiracy which will destroy the hyperspace lanes, making all of the planets of the poor (who cannot afford Faster Than Light drives of their own) to be cut off from the rest of the galaxy and quite possibly die off.
- Honnouji Academy in Kill la Kill has harshly separate, but socially mobile castes as part of its extreme approach to meritocracy. Most students are "no-stars", who live in a shantytown around the base of the academy. If they distinguish themselves in some way (usually by joining a club), they're given one-star uniforms and live in conditions comparable to the upper middle class. Two-stars, club captains and other members of the Absurdly Powerful Student Council, have Big Fancy Houses near the top of the facility, while the handful of Three-stars and the student council president live in the massive complex on top of the Academy.
- In Last Exile, the Guild are the ruling class of the planet who live in spectacular structures above the clouds and jealously preserve their advanced technology for their own use alone. The people living on the actual planet, on the continents of Anatoray and Disith, are forced to war with one another for control of the small (and thanks to the Guild's carelessness, shrinking) habitable areas. The Guild occasionally lends them weaponry to keep the war going, as they regard it as a source of entertainment. Only by the end of the story we learn that their world, Presteir, isn't actually a planet, but a giant space habitat built for evacuation of the Earth's population when the planet was hit by an uncertain cataclysm, and the Guild are essentially descendants of the transport spaceship crew, with the rest being the transported colonists.
- Its sequel, Last Exile: Fam, the Silver Wing, deals with the conflicts on the repopulated Earth, where the people who remained and weathered the cataclism the hard way are understandably wary of the returning Exiles, who compete for the not-so-abundant resources with the Guild (who still managed to remain influential) and stir the unrest further even there. Ironically, the cast of the original, who managed to reintegrate the Guildsmen into the wider society and thus wield their advanced knowledge and tech, are seen as the one of the most powerful factions in the story, while the larger Guild views them as dangerous rebels and rabble-rousers.
- In Tengen Toppa Gurren Lagann, the Beastmen live in the high-tech city of Teppelin under the rule of the Spiral King, while humans are forced to eke out an existence Beneath the Earth. The Spiral King maintains this to appease his masters, the Anti-Spiral, who want to keep humans from advancing because they are a Spiral race, and the awakening of Spiral Power could destroy the universe.
- In The Irregular at Magic High School, Earth is mostly normal except for the national tensions caused by magicians' existence. Governments are so desperate to keep the magicians they have from emigrating or having weak descendants that they are encouraged to socialize only with other magicians and unofficially above the law. In fact, many magicians are- knowingly or not- bioengineered clones of "real" people, created to serve their commissioners like slaves.
- In Lazarus, after an economic collapse and environmental problems, a small number of families have feudal control over the whole Earth, with a minority of slightly privileged serfs and most of the human race being abandoned as "waste".
- Elysium takes the "White Flight Syndrome" social phenomenon and boosts it way past Up to Eleven: the titular space station is essentially a suburb/man-made country for the hyper-rich to which they have moved to; leaving the increasingly-Crapsack World that is Earth (with its immense levels of overpopulated poor) to rot.
- Metropolis (1927) gives an early example, criticizing the trends of wealth accumulation and industrial dehumanization evident in the 1920s, and probably the Ur-Example of the Layered Metropolis. The ruling elite live like a sort of almost feudal nobility in the highest towers, in beautiful environments offering every educational and recreational opportunity. The deracinated prole workers, meanwhile, dwell in clockwork-orderly underground cities and wear drab uniforms, shambling about in "time-and-motion" lock-step and answering to service numbers rather than family names. In between, there is a middle class of professionals whose lives are fairly comfortable—But totally dependent on the goodwill of their elite masters, who can demote them to prole status on a whim.
- Nineteen Eighty-Four is probably one of the Trope Codifiers: the proles, who make up most of the population, are manual laborers with no privilege who live short and brutal lives, while party members get all the perks. Ironically, the proles are neither subject to the totalitarian control mandatory to the Outer Party members,note nor have to deal with the brutal power plays of the Inner Party, and are basically ignored by the ruling class except minimal supervision. As the local slogan goes, "Proles and animals are free".
- In The Caves of Steel, Earth is an overpopulated, poor planet with resources running out, and forced to implement Population Control, life in megacities, Future Food Is Artificial and Fantastic Caste System in order to survive. It is surrounded by fifty Spacer worlds; wealthy, low population, dozens of robotic servants per person...
- The Naked Sun introduces a planet which took it Up to Eleven; they boast an absence of social inequality due to a population of only twenty thousand people served upon by ten thousand times as many robots. There is a lot of Fantastic Racism on both sides, and it is stated outright that unless something is done, the tensions will lead to Earth's population being wiped out within the century.
- Existence by David Brin has the mid-21st century world stratified into ten "estates" based on wealth, with the first estate controlling by far the majority of the world's wealth despite comprising a very small fraction of a percentage of the population and acting like aristocrats.
- The Skaa in Mistborn: The Original Trilogy are a Slave Race who make up most of the population, live in slums, and are regularly abused if not casually murdered by the nobility, who regard them as subhuman.
- The Terahnee, seen in the Myst tie-in novel The Book of D'ni, take the cake for pointless malice. They're the descendants of the Ronay, who invented the ability to create Portal Books to any imaginable world. With this capability, they have unlimited access to land and resources, and indeed among their own kind even the very poor live in huge mansions, control land the size of a small country, barely work and spend most of their time in pursuit of the arts or playing extravagant games. However, the Terahnee decided that, with unlimited access to natural resources, the power source of their civilization should be slave labor. Because they see themselves as superior to other races, they enslave them and force them to work in backbreaking labor until death, while being carefully trained to never make a sound or be seen by their masters. In fact, the Terahnee consider themselves so superior to others that they're psychologically conditioned not to see other races. When a Terahnee first encounters the D'Ni the first thing he asks is: "Can I see you?".
- The Time Machine is one of the Trope Codifiers: in the distant future humanity has split into two groups, the Eloi (childlike humanoids who live an idyllic life on the lush surface and are the descendants of the rich) and the Morlocks (bestial people who dwell Beneath the Earth, provide food and clothes for the Eloi, and who are the descendants of laborers who were forced to remain there). The twist is that the Morlocks (at least by now) aren't a Slave Race, they're raising the Eloi as their cattle.
- Warhammer 40,000: Hive cities are homes to millions if not billions of people, who are richer the further up you go. Since hives are often the only habitable places on a Death World, the richest live in the upper atmosphere that's actually breathable, while the poorest have to fight off mutants, giant spiders and each other, feeding off the waste that gets dumped from higher strata. Unsurprisingly, the Imperial Guard recruits heavily from the scavenger population, since surviving to adulthood is no easy feat (and often develops other useful skills, like scrounging or a highly-developed sense of 3D direction).
- Warhammer: Bretonnia (King Arthur meets The Dung Ages) is essentially divided into two types of people: nobility and peasants (the other social classes of the actual Middle Ages presumably exist offscreen). The first are feudal overlords with their hands full dealing with orcs, Chaos and their neighbors encroaching, the second are illiterate, inbred Cannon Fodder whose only hope for social advancement is to join their lord's army as a bowman.
- The Kingdom of Zeal, occupying the era of 12,000 BC in Chrono Trigger, has a populace of elites inhabiting Floating Continents festooned with Crystal Spires and Togas, and use their powerful magic to make an easy life, while the "earthbound" without magic are forced to wear rags and live in caves. Things used to be more fair, until Queen Zeal rose to power and rearranged society around the worship of magic and its ultimate source, Lavos. They got their comeuppance, though: trying to use Lavos as a power source proved not to be a good idea and Zeal was sent crashing into the ocean (though the Queen got away physically unscathed and continued worshiping Lavos).
- In the backstory of Deponia, the elite population founded a floating city called Elysium and emigrated there en masse, leaving the poor to wallow in their waste on what quickly became a trash planet. After generations of separation, the Elysians became convinced that no life could survive on Deponia and planned to blow it up.