During this period, Kagetora succeeded to the family headship of Yamanouchi-Uesugi family and the post of Kanto Kanrei at Tsurugaoka Hachiman-gu Shrine of Kamakura Government on May 10, 1561, also at the request of Norimasa UESUGI, he changed his name to Masatora UESUGI.
しかし、この間に景虎は、上杉憲政の要請もあって鎌倉府の鶴岡八幡宮において閏3月16日、山内上杉家の家督と関東管領職を相続、名を上杉政虎（うえすぎまさとら）と改めた。