great doesn't have to mean this person was a nice guy. One can do terrible things and still be "great".

Some of the people that come to mind are:

Julius Ceasar
Hannibal
Napoleon
Genghis Khan
Atilla
Alexander
David


Plenty of others, tell us who you think and why.

you are either bored or drunk, either way, go to bed.

Thought it was an interesting topic. Contribute or you go to bed grumpy.

Alexander or Genghis kahn both did what noone has done since

it is, but its hard to imagine an answer for the question. Those Persian dynasties where some of the greatest.

You forgot Regan...

Constantine. Restored and reformed the Roman Empire and ensured its continuation for hundreds of years following his death.

The actor?

clearly regan the exorcist given the spelling.

I have a Stanley retractable ruler that has ruled for years.