Milky Way

The Milky Way (a translation of the Latin Via Lactea, in turn derived from the Greek Galaxia Kuklos) is the galaxy that contains Earth. It is home to several species influential to the history of the known universe, including the Goa'uld, the Tau'ri, and the Replicators.

The Milky Way galaxy is also one of the four known galaxies with a functional Stargate network, the others being Pegasus, Ida, and the Alteran Home Galaxy.

History
Millions of years ago, the Milky Way was colonized by the Ancients. Earth, the center of the Ancient presence in the galaxy, was used as the reference point for the Stargate network, with the coordinate system inspired by constellations as seen from Earth.

Approximately five million years ago, a virulent plague infected the Ancients that nearly wiped out the species. Originating at the construction site for their new capital known as Vis Uban, the deadly disease would spread across much of the galaxy. They attempted to travel back in time, to stop the plague from spreading, but their efforts were unsuccessful. Unable to cure it, the surviving Ancients left Earth in a huge space-borne city, which they called Atlantus.

Before leaving, the Ancients reseeded the Milky Way with life. As a result of this intervention, the Tau'ri &mdash; the "second incarnation" of Humans &mdash; evolved on Earth. By 9,177 BC, they developed primitive societies in isolation from the rest of the galaxy, as a result of not having access to the planet's original Stargate, which was buried under ice in the uninhabited Antarctica. This changed when the Goa'uld System Lord Ra discovered the planet and brought a second Stargate to transport Tau'ri slaves to Goa'uld-controlled planets.

By 3,000 BC, the Goa'uld had seeded the Milky Way galaxy with various Human races descendant from the Tau'ri, most prominently the Jaffa. It was at this point that the Tau'ri back on Earth rebelled against Ra, forcing him to bury his Stargate and abandon the planet.

Ra's Stargate lay buried until it was unearthed in 1928. In 1996, the Tau'ri activated their Stargate, and their first off-world expedition to Abydos, led by Colonel Jack O'Neill, confronted and killed Ra. This event created a power vacuum in the System Lord ranks, triggering a chain of events that eventually led to the downfall of the Goa'uld as the dominant power in the Milky Way.