The Internecine War was a large-scale gang war fought within Scatterhome in 461 A.E, between the two dominant gangs - the Ishbi Yardies and Haven's Children.
In centuries past, gangs effectively ruled different territories within the various asteroids and the Jin’s Blood Ark ship that make up Scatterhome. Any discipline its citizenry had enjoyed in the wake of its founding had devolved into near-tribalism. All-out gang wars were rare, but there was constant tension between them, with frequent small brawls and infrequent battles between scores of people. What made life tolerable for everyone else was the relatively small size of the gangs, which kept their predatory nature somewhat in check.
“Governing”, such as it was then, essentially functioned as rule of the jungle. If you could convince a big enough mob to do what you wanted, it got done. Skulls might end up being cracked, but it got done.
On issues of consequence, of course, your gang might have found one or more gangs actively opposing whatever it is your gang wanted, and so it became necessary for the various groups to stir up the other gang members and ordinary people and get them to join your cause. Gangs did this by putting the most verbally persuasive members of their roster in heavily-trafficked common areas, where they would, loudly and at length, call for the denizens of Scatterhome to join them in whatever cause it was they were championing. These were colloquially known as Callers, and what we know of those times tells us that it was an extremely dangerous job, for a good Caller could greatly augment the strength of a gang with their Calls, and so became an obvious target for a knife in the back, or a blaster to the gut.
As the years passed, these ‘Calls’ got much more sophisticated, and involved full-blown multi-media marketing campaigns designed to whip up the Scatterhomeans into an outraged fury and deliver mob justice to someone. This was expensive, and the smaller gangs couldn’t keep up, and in order to have any chance of seeing their agendas pushed forward, they would band together with gangs that they had something in common with, forming larger ones. By this process of accretion, gangs got bigger, had yet more resources to spend on Calling, and thereby to crush their enemies. This too accelerated the process, as if your gang’s dire enemy just doubled its size by merging with a rival gang, you better find a way to keep up.
Inexorably, over time, the gang composition of Scatterhome consisted of only two major gangs – the , and a few minor ones that were barely hanging on. The two majors – Haven’s Children and the Ishbi Yardies – were gearing up for the war everyone could see coming, and when it began, it was bloody.
The Internecine War, as it became known, wasn’t a war fought between disciplined soldiers executing a multi-front battle strategy. It began in 461 A.E. when one of the Yardies walked into a restaurant where a few Children were dining and dropped a thermal grenade, killing everyone in the place. It got worse. This was killing your enemy’s kids or cutting off power to entire sections of Scatterhome’s life support, hoping to muirder everyone inside those parts before power was restored. There were no rules, and nothing was too brutal. Each side seemed willing to escalate endlessly, and while each gang claimed territory, the reality is that they lived amongst each other, and so there was no “behind the lines.” Everywhere was the front line, and everywhere, gang members and ordinary citizens were being butchered.
Finally, a few members of the Children had the bright idea to dump some nerve toxins in the ventilation systems on Marle and Isbhi. They managed to deploy it on Marle, but before doing so on Ishbi, their homebrewed manufacturing rig for the toxins exploded and released the toxins into a crowded area on Haven, the stronghold of the Children. In one day, hundreds of Yardies and Children died, as did thousands of civilians.
The people of Scatterhome had had enough. They’d been terrified of the gangs, and were frequently collateral damage, but this was simply too much. Very quickly, they erupted into a mob larger than either of the gangs, and began beating, stabbing, or shooting to death any Yardie or member of the Children they could find, whether they were really sure the victim was in the gang or not. They died by the scores, as the gangs were much-better armed, but they had numbers on their side, as well as a sense of justified outrage, and they slaughtered hundreds of gang members to death before collectively issuing a demand: your leaders need to forever leave Scatterhome and the rest of you must disband or we won’t stop until we find every last one of you and toss your bodies out an airlock.
The remaining leaders of the Yardies and Children had no real choice. They weren’t shadowy, mysterious figures – everybody knew who ran the gangs. They fled, spreading to various dark corners of Starmourn, and, now rudderless, most of the gang members disbanded. The others generally wished they had before they were allowed to die.
Now, gang-less, the Scatterhomeans had to decide how to self-govern in a way that wouldn’t lead to the same outcome again. They decided that they didn’t wish to have a ruling class, or have elections in the way other civilizations did. They decided to preserve some of the spirit of the system of Calls, which is how Scatterhome got its modern form of government.
Ultimately, it's agreed upon that the end of the Internecine War and the formation of an agreed-upon method of self-governing that doesn't (usually) involve violence was the seed that later allowed Scatterhome to grow into a civilization on par with the Song and the Celestines.