Sima Yan was a prominent Chinese military leader and politician during the late Han Dynasty and the early Three Kingdoms period. He is best known for founding the Jin Dynasty in 265 AD after overthrowing the Cao Wei state. Sima Yan's rise to power marked a significant shift in Chinese history, as he united much of the territory that had been fragmented after the fall of the Han. Sima Yan was originally a member of the powerful Sima clan, which played a crucial role in the politics of the time. His leadership was characterized by efforts to consolidate power and stabilize the region, leading to a brief period of reunification in China. His legacy is often viewed through the lens of his family's continued influence in the Jin Dynasty and subsequent dynasties.