Humans Are Divided
Humans, moreso than other species/races, seem to be uniquely prone to factioning and/or inner conflict.
So you have your fantasy setting. The elves are all ruled by the gracious Queen Bona, the dwarves are all loyal to the mighty King Stormhammer, and the orcish hordes are all under the iron fist of Lord Grimdark. And the humans? Well, the humans have King James, King Seth, and King Ian. And they all hate each other. Humans, as a species, seem to be uniquely prone to factioning and intra-species conflict. If ever humans arise in a story, there are likely to be multiple kingdoms with poor relations. Multiple nations may exist for other races as well, but they usually like each other fine, unlike the humans, who will constantly try to get the edge on their "rival," even in the face of The Horde. Please note that this is only for cases where the humans are divided, in stark contrast to other races/species in the setting. If everyone hates each other, and the humans aren't special, then it's not an example.
- In The Lord of the Rings, Men are the only race to fight on both sides of the War of the Ring. The good side has Men of Dale, Gondor and Rohan, along with Dwarves, Elves, Ents and Hobbits. The evil side has Men of Dunland, Harad, Khand, Rhûn and Umbar, along with Orcs and other Always Chaotic Evil races. There was also a long-standing rivalry between Rohan and Gondor that slowed the building of their alliance.
- John Christopher's The Tripods trilogy. Before the Masters conquered the Earth humans regularly fought with each other as they do today. During the trilogy humans from different national areas joined together and carried out several attacks to defeat the Masters. Shortly after the victory the humans from different areas had already started squabbling with each other again, to the dismay of the narrator/protagonist.
- Spin Control by Chris Moriarty features a human-to-human example that is effectively Earthlings Are Divided. The bulk of human-controlled space is run by the United Nations, but Earth is hardly under a One World Order and its feuding nation-states present an unfamiliar wrinkle to offworlders trying to negotiate with Earth.
- In Harry Turtledove's Worldwar series the Race invades earth during World War II. America, the Soviets, and Nazi Germany only work together just enough to keep the Race from conquering the entire planet. And even then they're constantly at one another's throats.
- In the Garrett, P.I. series, humans are the only race inclined to prolonged large-scale conventional or magical warfare. Other races have the occasional internal spat, but it's usually either at the level of tribal feuding or else decided by a single battle. Civilized non-humans are more inclined to fight members of other species, or as mercenaries for human factions, than their own kind.
- In Ender's Game earth is united under the Hegemon thanks to the threat of the Formics, but the counter-invasion fleet hasn't even reached the Formic homeworld by the time countries start plotting against one another. And the planet is engulfed by war within months of the end of the war.
- In Babylon 5, the story arc starts with a unified human government called the Earth Alliance, which encompasses Earth and every other planet colonized by humans. However, by the end of the arc (after the Earth Civil War), Mars (which had a sizeable separatist movement since before the civil war) and some other colonies are independent entities. The Minbari also had a civil war, between castes in that case, but their race rather quickly reunified when that was settled. All other alien races were also under unified governments and stayed that way.
- In "Parliament of Dreams", they have a week in which each race on Babylon 5 is supposed to showcase the religion of their planet. All of the other races have a unified religion for their planet, but when it's the humans' turn to participate, Commander Sinclair walks the ambassadors down a long line of clergy from the multitude of faiths on Earth. Though it is shown in later episodes that the Narn have a few different faiths (or at least denominations emphasizing different prophets), and G'kar accidentally starts a new one.
- In Star Trek in general, when there is warfare within a planet, it is always described as "civil war", without regard to whether sovereign states are involved, in stark contrast to how we describe wars on Earth.
- In Battlestar Galactica (Reimagined) the twelve colonies of Kobol weren't politically unified until the Cylon rebellion. Amongst the refugee fleet infighting seems to kill as many as the Cylons.
- Andromeda: The Systems Commonwealth fell thanks to the Nietzscheans, a Human Subspecies, rebelling. Once the Commonwealth was shattered the Nietzscheans fragmented into hundreds of competing prides. Many of the assorted planetary governments during the Long Night are also human. In contrast the Vedrans all vanished, the Perseids retreated to their homeworld, the Than re-established their pre-Commonwealth Hegemony...
- Downplayed in Warhammer 40K. Humans are all united under the Imperium, but it's in a constant state of civil war (being so large) and their worlds are constantly at risk of being annexed by the Tau or falling to Chaos. However they're nowhere near as bad as the Orks (who'll fight each other if they can't find anyone else to have a scrap with).
- In Warhammer Fantasy humans comprise not only The Empire but also Bretonnia and much of the Chaos forces.
- The Dungeons & Dragons setting Eberron, of the twelve nations that formed from the breakup of the old Kingdom of Galifar, five are ruled by humans. Every other base race has one nation.
- Traveller has a lot of human empires. Due in part to the Ancient's habit of abducting primitive humans from earth and placing them on distant planets. During the reign of the Third Imperium there's the Imperium itself and its numerous client states, the semi-autonomous Solomani Confederation, the Zhodani Consulate, the Sword Worlders, the Darriens...
- Meanwhile the Hivers and K'kree have single unified states, while the Droyne live in scattered enclaves and the Aslan and Vargr seem incapable of forming stable large governments.
- While all the three races in Starcraft experience some Civil Warcraft the Terrans have it worst. Factions include the Terran Confederacy, the Sons of Korhal which become the Terran Dominion, Raynor's Raiders, and the United Earth Directorate. In contrast the Zerg are a Hive Mind who only fight one another when the Overmind's power is disrupted, and the Protoss have one major division who set aside their differences and reunite by Brood War.
- Warcraft II has the multiple human kingdoms, most of whom don't like each other, attempting to unite in the face of a united orcish Horde under the thumb of Orgrim Doomhammer. Gilneas ends up leaving, and Alterac eventually betrays them and joins the Horde.
- The X-Universe series has this happen due to Earth's colonies getting cut off from the homeworld. The four nonhuman core factions are all under One World Order, but by X3: Terran Conflict there are four separate human governments: the Argon Federation, the Earth State, the Free State of Solara (otherwise known as Aldrin), and the Hatikvah Free League. Earth's paranoia means that they and the Argon immediately become embroiled in a Space Cold War, which turns into a hot war by the next game Albion Prelude.
- In the Halo series the USMC was in the process of putting down many colonial insurrections when the multi-species Covenant attacked.
- In Command & Conquer 3: Tiberium Wars the GDI and Brotherhood of Nod are still fighting as the alien Scrin invade.
- Played With in Sword of the Stars, the Hivers, Tarka, and Zuul are more factional than humanity, but the Liir and Morrigi are more unified.
- Endless Space has three separate human factions; the capitalistic United Empire, the Pilgrims who broke off from the rule of the empire to pursue their own goals, and Horatio, who are all clones of a billionaire named Horatio, who decided to create an empire consisting entirely of himself. There's also a 4th human faction availeable as DLC, but background-wise it's the elite fleet of the United Empire and not a separate entity.
- Mass Effect has the Earth Systems Alliance and Cerberus, a very powerful terrorist organiztion (which becomes more powerful and openly hostile as the games progress). That said, the Krogan are even worse off, with the various clans fighting each other (they become united as the games progress), and the Turians are stated to have recently had their own internal conflict.
- When EverQuest II first launched, there were only two starting locations: The Human cities of Qeynos and Freeport. Both of these cities were the only ones that survived through 500 years of wars, cataclysms that tore up the entire planet, and one of Norrath's moons exploding and raining down debris. All the other races had to abandon their homes for various reasons and flock to those cities. With the continent literally split apart and separated by rough seas, a Cold War scenario developed between all the good races of Qeynos and all the evil races who fled to Freeport.
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