Board Thread:Show-Related Questions/@comment-25176701-20141207000831/@comment-6707115-20160409000759

The Heads of the Clans are more like Kings, Queens, Chiefs, etc. The Commander is more like an Emperor/Empress, especially given that they even have an Imperial Cult whereby they're seen as possessing a form of divinity (i.e. their collective spirit gets passed on, they're an avatar).

Also, the Latin word for Commander is "Imperator" (Imperatrix if female). It's where the word Emperor originally comes from.