The Yamanouchi-Uesugi clan was ousted from Kozuke and asked for help from Kagetora NAGAO (later, Kenshin UESUGI) and therefore the Hojo clan and the Nagao clan (later, inherited the Uesugi clan) struggled for Kanto.
山内上杉氏が上野を追われ上杉謙信（後の上杉謙信）を頼ったことから北条氏と長尾氏（のちに上杉氏を継ぐ）とが関東を巡って争った。