From Stargate Wiki
- "Yes, it's-it's the name of a dwarf galaxy in the local group."
- — Daniel Jackson
Pegasus is the name of an irregular dwarf galaxy in the Local Group located approximately 3 million light years from the Milky Way galaxy. Pegasus was also one of the first few galaxies visited by Destiny. There are numerous populations of humans in this galaxy seeded by the Ancients. These human populations are kept at a low technological state by the constant Wraith cullings and the threat of total annihilation if they were to resist the Wraith. As such many races in the Pegasus galaxy are small in number and several are known to be nomadic in nature as a means to avoid being culled.
Millions of years ago Pegasus was visited by the Ancient vessel Destiny and possibly the seed ships which may have deposited Stargates in this galaxy. Between 5 and 10 million years ago the Ancients abandoned the Milky Way and left in their city Atlantis, settling in the Pegasus galaxy. Here they built Stargates and placed them on many worlds, building outposts and spreading across the galaxy. The created humans and let them evolve on many planets, becoming renowned like gods among these populations. Inadvertently some of these humans were used as food for the Iratus bugs and over time evolved to become the Ancients greatest enemy, the Wraith. At some point the Sekkari civilization destroyed itself and they sent out seed carriers to reseed worlds with life. (SGU: "Air, Part 1", ATL: "Rising", "The Brotherhood", "The Gift", "Instinct", "Remnants")
Over time the Wraith became more powerful building ships and weapons and fighting the Ancients. The Ancient built ships too, much more powerful ones, but they were overconfident in their technology and started to lose ground to the Wraith superior numbers. The Wraith got their hands on some the Ancients ZPM's and used them to clone more warriors. The Ancients started to lose outposts and worlds to the Wraith until eventually Atlantis was all that remained. They remained sieged for many years until the Ancient decided to leave through the Stargate to Earth, leaving the city to slumber under the ocean. (ATL: "Rising", "Spoils of War", "Before I Sleep")
In 2004 the Atlantis expedition arrived on Atlantis and began to explore the galaxy meeting races on worlds and finding Ancient technology. The expedition fought against the Wraith and managed to significantly diminish their strength and numbers. They also reactivated the Asurans who further fought the Wraith as well as inadvertently killing some human populations. The expedition saved many people and made many allies, eventually the expedition left the galaxy in Atlantis to head off a hive ship on its way to Earth. (ATL: "Rising", "Progeny", "Lifeline")