I’ve always admired Alfred the Great. He may have only been a King, but I think he is worthy of elevation to Emperor, not due to territory, but achievement. He did a lot to improve England, seeing off the Viking threat, legal reform, military organisation, education and generally improving things for the populace. All the things that you might expect from a leader and rarely get.
The Emperor is not my favourite card, usually representing the kind of oppressive authority and subjugation that I really dislike, so I have tried to make it more the kind of authority with responsibility that I would like it to represent. A fatherly, benevolent and somewhat human figure, rather than a disciplinarian ruler.