Around this time, Shingen changed the traditional strategy to advance northward, carrying out the invasion of Shinano and Tokai region in alliance with the Oda family, and there was a conflict between some of his vassals and the group of Yoshinobu whose wife was the daughter of the Imagawa clan.
この頃信玄は従来の北進戦略を変更し、織田家と同盟して信濃侵攻や東海方面への侵攻を具体化しており、家臣団の中にも今川氏の娘を室とする義信派との対立があったという。