Thereafter, he served the Cloistered Emperor Toba, and being the husband of Emperor Goshirakawa's wet nurse, made efforts for Goshirakawa's return to power.
その後も鳥羽法皇に仕えた信西は、後白河天皇の乳母（紀伊局）の夫であることから、後白河の即位を実現させた。