A holographic depiction of the Krogan Rebellion
The Krogan Rebellion was a long conflict between the Citadel Council and the krogan.
History[]
In gratitude to the krogan for their help during the Rachni Wars, the Citadel Council granted the krogan control over conquered rachni planets and several uninhabited but very hospitable world. Having evolved on the harsh world of Tuchanka, krogan birth rates were exceptionally high in order to ensure their survival there. Without the drawbacks of their homeworld, the krogan experienced a massive population boom. They began to spread through the galaxy.
The Council was unconcerned by this until the krogan began to expand into territories claimed by other member species. The other species attempted to protect their worlds, but the krogan grew more aggressive. This came to a head when the krogan began to settle on the asari colony of Lusia. The Council ordered the krogan to leave -- and they refused. Their representative, Overlord Kredak, stormed out of the Council chambers -- and war followed.
The Citadel Council had prepared for this, establishing the Office of Special Tactics and Reconaissance less than ten cycles earlier. These Spectres began the war with guerilla tactics that slowed the advance of the krogan, employing computer viruses to utterly cripple the extranet the krogan used to coordinate. They sabotaged antimatter refineries, and struck space stations with suicide freighters.
Unlike the other species of the Citadel, however, the krogan could always rapidly replenish their numbers after a defeat. The war became one of attrition that the Citadel Council had no hope of winning.
Eventually, the Council sought the help of the turians -- a newly encountered species with tremendous military might. The turians were able to secure some definitive defeats against the krogan -- but the krogan responded with horrific force. They launched asteroids at turian colonies, and making three planets totally and utterly uninhabitable. This made the turians even more committed to defeating the krogan -- their doctrine demanded that they not only defeat the krogan, but stop them from ever becoming a threat again.
The turians contacted the salarians, who were developing a bio-weapon called the genophage which was meant to introduce a genetic mutation into the krogan genome that would limit their birth rate -- only one in every thousand births would be able to survive.
It was intended to be a deterrent against the krogan, but the turians had other plans -- in 1510 CE, they unleashed the bio-weapon on their enemy. The krogan numbers began to dwindle -- and as this realization dawned on them, they found themselves beset on all sides by turian forces.
The krogans attempted one final stand -- a fertile female warlord named Shiagur gathered all of the best krogan warriors she could find and fought the turians at the Battle of Canrum. She was slain there. Krogan men killed all of the turians involved in revenge -- but Canrum proved to be the last effort of the Krogan Rebellion. The krogan surrendered.
Source[]
The Krogan Rebellion is derived from Mass Effect. For more information, please visit Mass Effect Wiki.