I kind of figured the empire would already exist but wouldn't have much infulence.
It would be the acquisition of Vader that would make the Empire the greatest power in the galaxy.

Episode 1: Ancient history, the old republic, the jedi order
Episode 2: The clone wars, Obi-wan and Anakin first meet, Anakin begins his training. Yoda is mentioned but not shown.
Episode 3: Anakin becomes Darth Vader, the emperor uses him as his harbinger and takes over the greater galaxy

Or however it was in the EU, i havent read it

I want to though

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