Rachni Wars
The century the galaxy nearly fell
The Rachni Wars were a series of conflicts beginning around 1 CE, after a Citadel expedition opened a dormant mass relay into the territory of the rachni, a hostile hive-minded insect species. The Council races fought a losing war for nearly a century until the salarians uplifted the krogan, whose numbers turned the tide and drove the rachni to extinction.
The Rachni Wars were a series of conflicts that began around 1 CE, when an expedition from the Citadel Council activated a dormant mass relay and opened a route into territory controlled by the rachni, a species of highly intelligent, hive-minded, space-faring insects. Alarmingly powerful and utterly hostile, the rachni could not be reasoned with, and the war that followed nearly overwhelmed the galaxy before the uplift of the krogan turned the tide. (Mass Effect)
Discovering the rachni#
Around 1 CE, salarian explorers opened a mass relay into a previously unknown system and encountered the rachni, who promptly captured them. Using extensive research on element zero, the rachni reverse-engineered the FTL drives of the explorers' starships, built FTL vessels of their own, and rapidly spread into the wider galaxy, beginning the wars. Every attempt by the Citadel races to negotiate failed, for the rachni were guided by hive queens that dwelt in deep nests beneath the inhospitable surfaces of their worlds, where no one could reach them. Concluding that the rachni were irredeemably hostile and could be stopped only by force, the Council races went to war, but the insects' sheer numbers overwhelmed every defense. (Mass Effect)
Uplifting the krogan#
For nearly a century the Citadel races fought a losing war. To find soldiers who could match the rachni, the salarians culturally uplifted a new species, the krogan. The krogan homeworld, Tuchanka, had been left a radioactive ruin by a nuclear winter following a krogan civil war, and the salarians gave the krogan advanced technology and relocated them to a world free of the lethal radiation, toxins, and predators of their home. (Mass Effect)
The true purpose of this generosity soon became clear: the krogan were needed as reinforcements. Unlike most Citadel species, they bred with extraordinary speed, giving them both the numbers to drive the rachni back and the resilience to endure the deadly conditions of the rachni worlds. (Mass Effect)
Extermination#
The krogan struck at the queens in their lairs and swiftly reclaimed the conquered Council worlds. When their fleets pushed the rachni back to the homeworld Suen, the insects refused to surrender. The krogan response was swift and total: they bombarded Suen's cities and detonated powerful bombs within the rachni's underground nests, obliterating them and leaving vast sinkholes across the planet's surface. The Council would ordinarily have objected to such complete destruction, but after a century of relentless war, the eradication of the rachni seemed the only solution. (Mass Effect)
In 300 CE the rachni were declared extinct, though as a precaution the Council left a listening post in their home system to watch for survivors. In the aftermath the Council established new policies forbidding the activation of any dormant mass relay that led to uncharted systems, so as to prevent another disastrous encounter with an undiscovered species. It was the first great conflict of the Council era on the Mass Effect timeline. (Mass Effect)
Disputed origins#
In later years it was postulated that another party, possibly the Reapers, had manipulated the rachni into starting the war. A surviving Rachni Queen recovered during the era of Commander Shepard described having heard, while still in her egg, only the sounds of oily shadows and a tone from space that hushed one voice after another and forced the singers to take up its own sour note, an account reminiscent of Reaper indoctrination. The researcher Dr. Garret Bryson later suggested the mythical Leviathan was responsible instead, perhaps seeking to raise an army against the Reapers, reasoning that the Reapers had been in dark space at the time and the ancient rachni bore no trace of the cybernetic augmentation the Reapers used to convert organics. His theory was never confirmed. (Mass Effect; Mass Effect 3: Leviathan)
Frequently asked questions
- What were the Rachni Wars?
- The Rachni Wars were a series of conflicts that began around 1 CE, when a Citadel expedition activated a dormant mass relay and opened a route into territory controlled by the rachni, a species of hive-minded, space-faring insects. The hostile rachni could not be reasoned with, and the war nearly overwhelmed the galaxy.
- How did the Rachni Wars start?
- Around 1 CE, salarian explorers opened a mass relay into a previously unknown system and were captured by the rachni. Using their element zero research, the rachni reverse-engineered the explorers' FTL drives, built their own fleets, and rapidly spread into the galaxy.
- Why couldn't the Council negotiate peace with the rachni?
- The rachni were guided by hive queens that dwelt in deep nests beneath the inhospitable surfaces of their worlds, where no one could reach them. Concluding that the rachni were irredeemably hostile, the Council races went to war, but the insects' sheer numbers overwhelmed every defense.
- How did the krogan turn the tide of the Rachni Wars?
- After nearly a century of losing, the salarians culturally uplifted the krogan, relocating them from their radioactive homeworld and arming them with advanced technology. The krogan bred with extraordinary speed and could endure the deadly conditions of the rachni worlds, letting them strike at the queens in their lairs and drive the rachni back.
- How did the Rachni Wars end?
- When krogan fleets pushed the rachni back to their homeworld Suen, the insects refused to surrender, so the krogan bombarded the cities and detonated bombs in the underground nests until the species was destroyed. The rachni were declared extinct in 300 CE, and the Council banned the activation of any dormant relay leading to uncharted systems.
Sources
- GameMass Effect, BioWare, 2007
- GameMass Effect 3, BioWare, 2012
- GameMass Effect 3: Leviathan, BioWare, 2012, downloadable content
Spotted a factual error or a primary source we missed? Email a correction. Every flagged claim gets reviewed.
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