The Ori (pronounced or-eye) were the first evolution of humanity, along with the Ancients. Originally known as the Alterans, they later learned how to ascend and used their knowledge and power as a justification and a means to demand the worship of mortal beings.

Millions of years ago, the Ori lived together with the Ancients as a single, united society in a distant galaxy as the Alterans. At some point, however, a split occurred among the Alterans: The Ancients began to devote themselves to science, while the Ori became increasingly religious. This division eventually became so great that the Ori attempted to destroy the Ancients. To avoid a war, which was contradictory to their beliefs, the Ancients departed their home galaxy for the Milky Way.

Even after they left, the Ancients and the Ori remained enemies: Daniel Jackson believes that the Ori were responsible for the plague that nearly brought the Ancients to extinction in the Milky Way and forced them to leave in Atlantis for the Pegasus galaxy. Both the Ancients and the Ori eventually ascended, and the Ori passed on a religion called "Origin" to the next evolution of humans they created in order to increase their own power, using their ascension and knowledge of the universe as justification for praise and worship. (Read more...)