The Old Republic Timeline 6: Onslaught of the Sith Empire is the sixth in the series of in-universe videos, providing backstory for the Star Wars: The Old Republic video game. The video is presented in the form of a record entry made in the Jedi Archives by Jedi Master Gnost-Dural.

It can be viewed here:

https://youtu.be/vHCPju6amQQ