Related Clues:

• Big business
• Royal domain
• It's under imperial dominion
• Roman, say
• Powerful ruling period
• Part of HRE
• Darth Vader's dominion
• Big realm
• Wide domain
• See 90-Down
• Vast realm
• Supremacy
• Caesar's domain
• It's defeated in 'Return of the Jedi'
• Napoleon's realm, e.g.