Depends on your definition of "great."
The most objective definition is determined by the person's impact on history, not their goodness.
By that definition all the "great" monsters of history were great men. Alexander, Atilla, Hitler, Mao, Stalin, Lenin, etc.
Napoleon was not a good man, by any definition I can think of. But he most definitely was a great man, with great accomplishments in multiple fields. Military, law, civil administration, armed robbery, looting, etc.
And he was probably the greatest soldier of all time. France had for centuries been fighting with its neighbors over a few square miles of borderland. Under Napoleon it conquered all of Europe. Were it not for 10 miles of saltwater, he might have conquered the entire world.
Though to be fair the revolutionary regime had already performed astonishing military feats before Napo came along.
“Were it not for ten miles of salt water....”
.
You seem to forget the Russian winter.