Who is Sima Yi?

Emperor Sima Yi (179-25 1), of Han nationality, was born in Xiaojinli, wen county, Hanoi County (now wen county, Henan Province). Wei was an outstanding politician and strategist in the Three Kingdoms period and the founder of the Western Jin Dynasty. He used to be the commander-in-chief of Cao Wei, Qiu and Taifu. He was an important minister who assisted the three generations of Wei, and later became a minister in charge of Wei's state affairs. The greatest achievement in my life is that I led the army to successfully fight against Zhuge Liang's Northern Expedition many times. After his death, posthumous title Wuyang Xuanwenhou, the second son Si Mazhao was named as the Queen of Jin, and Sima Yi was named after him. After Sima Yan proclaimed himself emperor, Sima Yi was honored as Xuan Di.