Sith Origins: BEFORE Darth Bane

Before Darth Bane created the Rule of Two, there was a Sith Lord who united hundreds of Sith warriors to fight a bloody galactic war against the Old Republic. Who was this Sith Lord? And how did he unify the Sith, getting them to put aside their lust for power and infighting with each other for the good of the Dark Side? We'll find out in this episode of Star Wars Theory.