"Then one day our people stepped foot upon a dark world where a terrible enemy slept. Never before had we encountered beings with powers that rivaled our own... and in our overconfidence, we were unprepared and outnumbered."
The Lantean-Wraith War was a conflict that erupted in the Pegasus Galaxy roughly 10,000 years ago between the Lanteans and Wraith for dominance of the entire region. The war lasted over a century and cost untold trillions of lives, but the technological superiority of the Ancients was useless against the incredibly numerical advantage of their enemies. Unwilling to favor strategy over morality, the Lantean fleet was pushed to the breaking point as it tried to defend thousands of human worlds on hundreds of fronts. In the end, the Wraith were able to simply overrun their adversaries and lay siege to Atlantis itself, forcing the Ancients to evacuate to Earth and surrender the galaxy. With no one left to stop them, the aliens commenced with the first Great Holocaust, terrorizing the defenseless humans and solidifying their iron grip on Pegasus.