The period known as the Gank Massacres spanned from 4800 BBY until 4775 BBY.
Following the unveiling of Ryll, the Neimoidians secured the rights to distribute this substance. A newly encountered species, the Porporites, rapidly developed an addiction to ryll, driving them into a state of murderous rage. In an attempt to quell the Porporites, the Galactic Republic deployed both Jedi Knights and standard military forces, yet the Porporites resisted all Republic efforts. Fearing for their well-being (as well as their profits), the Neimoidians engaged several Gank mercenaries for protection. Regrettably, the Ganks determined that the most effective strategy was to exterminate the Porporites. Subsequently, the Ganks initiated a widespread war against the Republic. Supreme Chancellor Vocatara was then compelled to order the construction of Juggernaut war droids in order to bring the conflict to an end.
This period of massacres also marked the initial deployment of modern lightsabers, which operated independently of the power packs utilized during the Great Hyperspace War approximately two centuries prior. Furthermore, the Republic rocket-jumpers participated in the conflict as part of the Republic's armed forces.
Jedi Master Shayoto made reference to the Gank Massacres during the Conclave at Deneba, which took place in 3997 BBY.