The Great Khan! He took the hunting practices of his nomadic people and forged them into a battle doctrine that conquered half the world (or at least the heartland of the Chinese, Central Asian-Persian, Islamic, and Russian cultures)!
Seriously, he WORKED and he worked hard to forge his empire. His father was killed when he was a kid, he and hisfamily were banished from their tribe, he freed the slaves of the tribe that was his mortal enemy, when his father in law tried to reinback on offering his daughter to him he went out and got her; and constantly messed up anyone who decided to mess with him personally! So much so he created the largest Empire to the dateand still one of the largest land empires encompassing several civilizations and culminating in truly world changing events from the black plague to the destruction of Baghdad to the Yuan then Ming Dynasty to making everyone in Europe from all the peasents to the Pope shit themselves at the thought of him and his empire....!