"I'm sorry, you hairless apes did WHAT?" - Rhea Canel, head of the CNK Institute yet somehow unaware of the Charlemagne Disaster.
The Charlemagne Disaster is easily the worst manmade disaster in recorded history.
A subspace detonation occurred during an attempted Terran invasion. This detonation was so large that it rendered the entire system inaccessible. The explosion is, thanks to the horrific warping of spacetime in the system, still happening and researchers onsite believe that it is unlikely to cease any time soon.
This disaster brought both the Terrans and the League to the negotiating table and the current cease fire is a direct result.
The Charlemagne Accords also established the Carolingian system as a Galactically Protected system, the first of its kind, and now plays host to research stations from all five governments.
Discovered in the early 2300's by an independent exploration guild, the Carolingian system plays host to a staggering three planets in the habitable zone, none of which need substantial terraforming to become ready for human habitation. The system also holds a rare-earth rich asteroid belt and a unique binary gas giant pair, both rich in Helium-3.
These findings alone would have made the system a highly valued one, however, the true gem was the planet Charlemagne.
Sitting in a prime position as the fourth planet out from the local star, Charlemagne was likely always going to end up a habitable planet for humankind. Thanks to the very minor axial tilt and its distance from the local star, Charlemagne maintained a temperate climate that, outside of the extreme polar regions, fluctuated between Southern California and the Pacific Northwest.
Charlemagne's flora and fauna were almost suspiciously close to Earth's. A popular conspiracy theory suggested that Charlemagne was actually prepared for human colonization by some ancient, near omniscient beings who still observe the galaxy like some sort of long-term experiment. There being no real evidence found for such a claim keeps it from gaining any serious consideration.
Genetically, the flora and fauna of Charlemagne was almost perfectly suited for human digestion. Settlers only needed to take a small supplement for the first year of their residency on the planet to fully acclimate their systems. This was just this side of a miraculous occurrence in the galaxy and as such, Charlemagne redefined what an Eden planet should look like.
Outside of its near-perfect-for-humans climate and native lifeforms, Charlemagne was also an incredibly mineral-rich planet. The initial wave of settlers made the conscious decision to limit the amount of mining that could be done, and as a result, mining technology underwent a quantum leap in development as corporations were desperate to get their hands on the wealth of the planet.
The Carolingian system was deep enough into what eventually became the Confederacy of Freelance States that they never worried overly much about the war between the League and the Terrans. When the Sixth Interstellar War broke out, the Carolingian system accepted the offer of the League and the Confederacy to house a small force from both governments in-system, though they still maintained that they were far enough away from Republic space to not be a likely or viable target.
For most of their history, this assumption was entirely correct. The Republic was largely unwilling to push that deep into Confederacy space without first absorbing the systems in between.
At the end of the Sixth Interstellar War, the Republic was on a military upswing and many believed that this conflict may well have been the one to see the Republic pull many systems into itself. No one expected the three deep thrusts that Terran High Command made instead of trying to push back the frontlines.
The Carolingian system was one of those three thrusts, with the other two being Gaelia and Trajan, both of which were intended to be faints to draw forces away from Charlemagne.
On August 8th, 2641, at 0530 hours (Sol Standard Time), the Terran Republic's 438th Fleet exited subspace near Charlemagne high orbit and immediately engaged the League and Freelance defenses who were caught off-guard by their enemy's sudden arrival.
By 0545, the battle had been joined in earnest, with the Freelance command ship under heavy fire by the TRS Moskva and her two battleships.
By 0605, the League forces under Admiral Adrian Reach were considering a tactical withdrawal and the Freelance forces were largely in disarray. Two of the four Republic Valorous-class cruisers, the Cairo and the Memphis, were moving away from the main battle to begin deploying themselves into their station configuration. By any reasonable measure, the battle was almost completely won for the Republic.
At 0615, Admiral Reach officially sounded the retreat for the League and began pulling his forces away from the planet to jump out of the system. A single Freelance cruiser began moving away on a heading that would give them a clear jump to Gaelia. The Moskva moved to intercept.
At 0618, the captain of the TRS Bulawayo reported a problem to the captain of the Moskva. Their reactor was showing signs that it had been tampered with and was heading towards a runaway detonation, which should not have been possible.
At 0621, the Admiral of the Republic Fleet, Marius Qadir, who's flag was currently on the Bulawayo, ordered an immediate system-wide evacuation of all Terran forces, as the same sabotage that turned their reactor into a bomb had become evident in the Bulawayo's grav drives as well. Admiral Qadir almost immediately extended the broadcast to every emergency channel in the system, attempting to alert the League, Freelancer, and civilian vessels of the danger. Admiral Reach responded with sensor confirmation and urged all vessels to abandon orbit immediately.
At 0623, the Moskva, Cairo, and Memphis all jumped out of system. They were followed by the two League ships that could dive into subspace (the LXS Cernunnos and the LSS Dagda), the one fleeing Freelance cruiser, and twelve civilian ships.
At 0625, the Bulawayo's reactor went thermonuclear and her grav drives engaged. This resulted in a subspace detonation that was detectable by all of the ships currently fleeing the system. Admiral Reach utilized the powerful grav shields on the LSS Odin to give the fleeing civilian ships a few precious seconds to escape ahead of the blast. The Moskva, Cairo, and Memphis all dropped out of subspace on the outer edge of the Carolingian system's heliopause, and even at that distance, their sensors could pick up the intense energy rippling around the system.
At 0630, the Moskva ordered the Memphis and Cairo to make best speeds for Earth and Calysto respectively while they remained on station to observe.
It took a while for the various governments of the Galaxy to fully grasp what had happened. The Memphis arrived at Earth roughly 70 days after the accident, having pushed as hard and fast as her captain was willing to push her without her reactor melting down. The Cairo arrived at Calysto 92 days after the disaster with her grav drive failing and found that they had arrived just before the LXS Cernunnos and the LSS Dagda who corroborated their story.
Communications flew between the three human Governments, eventually expanding out to include the NorAellian and Lyndri, and a temporary cease fire was offered by the Terrans as they all needed to evaluate what had occurred. The Confederacy and the League were hesitant to accept this offer as it suggested that the Republic felt that they had gained control of the system in question. It took the mediation efforts of the NorAellians before a delegation, consisting of the heads of state of all five nations plus scientific and military advisors from each as well, was assembled on the NorAellian flagship.
This delegation arrived at the Moskva's position on January 18th, 2642. By this time, the detonation was visible from where they held at the edge of the heliopause and the spacetime warping was easily detectable. The Moskva reported that, despite their warnings, five civilian ships had attempted to enter the system. Two of them were destroyed in subspace, and the other three were ripped apart by the spatial warp just inside the heliopause.
At the time of the disaster, the total population of the Carolingian system was sitting at just over one billion people, including the crews of the ships battling in orbit. Of that total population, only 1,746 people escaped the system before the Bulawayo detonated.
It did not take long for the delegation to acknowledge that everyone in-system was, if not outright dead, then trapped within a spacetime tangle so extreme that there was little chance of anything making it in or out of the system. They declared everyone in residence who was not one of the survivors missing-presumed-dead and sent official declarations of mourning out to their respective citizens.
On January 21st, 2642, every sentient in the galaxy was asked to have a moment of silence in memorial of those lives lost at Charlemagne. On January 22nd, 2642, the delegates sat down and ratified both an official cease-fire on the Sixth Interstellar War and the Charlemagne Accords.
The Charlemagne Accords are the first of their kind in galactic history. It represented the very first time all three sentient races in the galaxy and their five associated governments sat down together and ratified a mutually binding treaty. It also represented the very first time that all five governments unanimously declared a potential weapon to be so devastating that it would never be used deliberately.
The first thing that the Charlemagne accords did was institute a cease-fire among the human governments. Neither the League nor the Republic were seeking a full cease-fire, however, it was the NorAellian's price for their support of the Accords.
The cease-fire officially went into effect six months later, in July of 2642, giving both governments the opportunity to recall any active operations and pull their forces back to within their established boundaries.
As an interesting historical side-note, this was the first cease-fire between the two dominant human governments that did not include any trading of territory or exchange of prisoners. The NorAellians simply told them to keep what they had claimed, to make offers of prisoner trade later, and just, in the words of the NorAellian Alpha Prime, "stop your petty squabbles for one damn minute and let us address something of actual importance."
This cease-fire would be one of the longest to exist between the disparate forces of humanity, lasting all the way to the Tel'Erani incident in February of 2695.
Of greater import than the cease-fire was the unanimously agreed upon ban of subspace weapons. Even today, some 50 years later, the specter of Charlemagne looms large in the collective minds of the galaxy. All subspace research was halted for five years to assess if any of it was moving towards weaponry of any kind, and where it was, the research team was retasked and the problematic material was removed to that nation's research station on the outskirts of the Carolingian system.
This research assessment is still carried out regularly in all five nations, and is done so by representatives from all five nations as well. In this one, specific area, a sort of galactic unity has been achieved. Corporations, from small start-ups all the way to megacorps, allow the assessors to review any and all subspace research. Even minor, unattached systems or clusters will invite the assessors to look over their research.
In a deeply revealing interview released on the 25th anniversary of the disaster, the interviewer asked the NorAellian Minister of Subspace Research, who volunteered to be interviewed, if they thought that this avenue of cooperation could be used as a blueprint for complete galactic unity. Their response was "No. I certainly hope that it never is. This one facsimile of unity is not a genuine expression of international cooperation or an expression of any government's desire to unite with any other. It was done out of fear and under threat and no foundation for lasting unity should ever be built on such unstable surfaces as those."
Those concerns are shared by many governmental figures across the galaxy, and more than once, a proposal has been floated to try and give the research assessment group a more stable foundation, but to date, no proposal has been accepted.
Still, despite these concerns, the ban has yet to be violated. A lot of research has been reviewed and a small fraction of that research has been transferred to the Carolingian Research Stations for preservation or to aid in the work being done there.
The Accords designated the Carolingian system as the very first Galactic Protectorate. This unique designation means that, for safety concerns, the entire space within the system's heliopause is off-limits for any and all transversal. Owing to the way that grav drives function, this is not a difficult rule to enforce. All subspace routes that once cut through the system have been rerouted and the entire system is considered a navigational hazard that any up-to-date navigation system will avoid.
In a technical sense, the entire system has more or less been declared a preserve monitored by representatives from all five major governments.
This doesn't mean that people don't try, however. Every Sol Standard year, at least two ships are lost to the subspace tangle that the Carolingian system has become. Usually, these are reportedly ill-maintained ships who may be flying without HazNav avoidance activated. Sometimes, it's some ammeter scientist convinced that they found a way to navigate the spacetime warp that fills the system.
To date, no ship that has entered the system since the Moskva first setup a HazNav beacon has emerged from it. Theories range from nigh instant destruction all the way to a temporal warp that is functioning like some extreme form of time dilation. We may never know the full truth of it, though that doesn't mean that people aren't trying.
Along with serving as the patrolling force keeping people away from the dangers that the Carolingian system represents, each nation maintains a research station located at equidistant points on the edge of the system's heliopause. These stations are populated by the crews and support staff of the patrol vessels along with some of the largest single-focus scientific teams ever assembled.
Each of the five nations designed, built, and populated their own stations. The only exception to this is the Lyndri station. While it was designed and built by the Lyndri, it is populated by Lyndri, NorAellian, and humans. The Lyndri possess a navy of their own, however, due to their low number of ships, they asked for, and were granted, a dispensation by the other four governments to request assistance in fulfilling the stations role.
On the patrol side, the Lyndri reached out to the League and the NorAellians and asked if they would handle the patrol zone assigned to the Lyndri station. Both nations agreed. On the research side, the Lyndri initially sought out a multi-national group of researchers. Years later, after the founding of the Corona Noir Ki Institute, the Lyndri were approached by the Institute's Director who was seeking to be the exclusive research organization on the Lyndri Station.
These research teams have been working on unraveling whatever is happening in the Carolingian system.