Cao Cao was a warlord and the penultimate chancellor of the Eastern Han Dynasty who rose to great power during the dynasty's final years. As one of the central figures of the Three Kingdoms period, he laid the foundations for what was to become the state of Cao Wei and was posthumously titled Emperor Wu of Wei. Although often portrayed as a cruel and merciless tyrant, Cao Cao has also been praised as a brilliant ruler and military genius who treated his subordinates like his family. He was also skilled in poetry and martial arts and wrote many war journals.