Quick overview of History

The Ancients Created the Stargates and lived on earth

The Ancients left earth and Went to the Pegasus Galaxy

The Ga'uld Enslaved the race known as Unass of which the Yautja were an advanced strain

The Ga'uld took over earth

The Yautja and Humans overthrew the Ga'uld, the Yautja took what technology they could and claimed themselves rulers of earth setting up the laws of the hunt

The Yautja left Earth and humanity flourished

The Ancients populated the Pegasus Galaxy with humans but were defeated by the Wraith

The Ancients fled back to earth to live out the rest of their lives but a small faction fled to another galaxy and renamed themselves the Xel Naga

The Xel Naga created the protoss and lived with them until the protoss became corrupt

The Xel Naga created the Zerg

the Zerg destroyed the Xel Naga

The Yautja Began Using the Stargates on their hunts

The Yautja met the Wraith deeming them an acceptable prey

The Humans began using the stargate

The Humans fought the Ga'uld and came in contact the the Unass species

The humans went to the pegasus galaxy and met the wraith

The Yautja were reunited with their Unass cousins

Centuries passed, the Humans sent their weak and criminal to another galaxy

The Banished humans flourished and met the Protoss

The Humans met the Zerg

The Yautja met the Zerg and deemed them acceptable prey

The Yautja met the Protoss

The Covenant attacked one of earth's colonies

The Tri-Galactic war began (Covenant, Ga'uld, Humans, Protoss, Wraith, Yautja, Zerg and many more)