Jiang Wei is a general of the Three Kingdoms era who first served Ma Zun. He surrendered to Shu when his station was attacked and was praised by Zhuge Liang. Jiang Wei took it upon himself after the Prime Minister's death to keep waging war with Wei in the north. Even with Liu Shan's surrender to Deng Ai, Jiang Wei would oppose Wei until his death. He is Zhuge Liang's lone and trusted successor in Romance of the Three Kingdoms and one of the novel's tragic figures.
from the koei Wikipedia.