Apparently, until the beginning of the Edo Period, the Gohojo clan was thought to have originated from the Ise clan but from the mid-Edo Period, influenced by the "Taikoki," a biography of Hideyoshi TOYOTOMI, the view of Soun as a lowly samurai in the Warring States Period, who came to power through his achievements in the so called 'Gekokujo Period' caught the public's imagination, becoming well-established in the Meiji Period and prevailing until the end of WWII.
江戸時代前期までは後北条氏は名門伊勢氏の出と考えられていた様子だが、江戸時代中期以降、『太閤記』の影響で戦国時代を身分の低い者が実力で身を興す「下克上の時代」ととらえる史観が民衆の願望もあいまって形成され,明治時代になって定着し、戦後まで続いた。