The Hojo Clan Residence Ruins mark the site of the estate that the Hojo — the family who would sustain the Kamakura shogunate — made their base in Izu. Hojo Masako was born and raised as Tokimasa's eldest daughter in this land of Hojo, and here she met and was united with Minamoto no Yoritomo, exiled to nearby Hirugashima after the Heiji Rebellion. Defying her father to run to Yoritomo's side, Masako became the wife of the first Kamakura shogun and, after his death, guided the shogunate as the "Nun Shogun." The starting point of that life was this very residence of the Hojo.

Hojo Yoshitoki was born and raised at this Hojo residence as the son of the first regent Hojo Tokimasa and the younger brother of Masako. When his sister Masako was united with Minamoto no Yoritomo, the Hojo backed Yoritomo's uprising, and Yoshitoki too served close to Yoritomo from a young age. He would go on to become the second regent (shikken) of the Kamakura shogunate, prevail in the Jokyu War, and lay the foundations of a warrior government that eclipsed the imperial court — and the origin of that career lies here in the land of Hojo in Izu.

The Hojo Clan Residence site in Izu-Nirayama is the birthplace of the Kamakura Hojo, the family that produced the first shikken (regent), Hojo Tokimasa. It was here that the exiled Minamoto no Yoritomo married Tokimasa's daughter Masako; by backing Yoritomo's uprising, Tokimasa set the Hojo on the path to controlling the shogunate.