Cao Cao rose to power during the final years of the Eastern Han dynasty, controlling the figurehead Emperor Xian.
He secured northern China with a decisive victory at the Battle of Guandu in 200 AD, defeating traditional rival Yuan Shao.
Though his southern ambition was shattered at the Battle of Red Cliffs in 208 AD, his state of Wei became the most powerful of the Three Kingdoms.
His legacy in history is mixed, celebrated as a brilliant statesman and poet, yet vilified in the 'Romance of the Three Kingdoms' as a cruel tyrant.