He was born the heir of Ise Sozui (Hojo Soun). His mother is said to have been a daughter of the Ogasawara. His father was rising in Suruga as a relative of the Imagawa, and Ujitsuna grew up as heir of a house becoming a Warring States lord.
Around this time his father Sozui is said to have taken Odawara Castle in Sagami. Dates vary, but Odawara became the base of five Hojo generations. From boyhood Ujitsuna watched his father's campaigns extending power into Izu and Sagami.
With his father he besieged the old Sagami house of Miura Dosun and his son Yoshioki at Arai Castle and destroyed them after a long siege. Nearly all Sagami became Hojo land. Ujitsuna fought at the center and showed his strength as the next head.
His father retired and Ujitsuna became head. From about this time orders went directly to subjects in documents bearing the tiger seal, said to curb arbitrary levies. It began the careful domain rule of the Hojo.
His father Sozui died. Ujitsuna inherited the Izu-Sagami domain and secured rule with land surveys and protection of temples and shrines. Outside stood the old Kanto house of Uesugi, and a long struggle to push into Musashi began.
Around this time he changed the family name from Ise to Hojo. By taking the name of the Kamakura regents, he is thought to have sought to show his right to rule the Kanto. Thus arose the house called the Later Hojo.
He captured Edo Castle in Musashi, held by Ogigayatsu Uesugi Tomooki. Built by Ota Dokan, it was a key fortress, and the Hojo pushed deep into Musashi. Fierce struggles with the Uesugi and the Takeda of Kai continued afterward.
He began rebuilding Tsurugaoka Hachimangu in Kamakura, burned in war, mobilizing warriors and craftsmen across the Kanto and finishing in 1540. Reviving the Minamoto shrine also aimed to show widely that the Hojo were guardians of the Kanto.
He seized Kawagoe Castle in Musashi, base of Ogigayatsu Uesugi Tomosada. Ogigayatsu power was badly cut, and the Hojo held most of Musashi. Kawagoe later became the stage of his son Ujiyasu's night battle that crushed the Uesugi alliance.
At Konodai in Shimousa he defeated the forces of the Oyumi kubo Ashikaga Yoshiaki and Satomi Yoshitaka of Awa. Yoshiaki fell, and Ujitsuna won the trust of the Koga kubo Ashikaga Haruuji. He later married his daughter to Haruuji and is said to have been named Kanto deputy, raising his standing.
Before dying of illness he is said to have left his son Ujiyasu a five-article testament. It urged keeping righteousness, caring for retainers and people, and avoiding luxury, and is said to have become a model for the Hojo house style.
Ōta DōkanHōjō UjiyasuTaigen Sessai
Hōjō Sōun (Ise Sōzui)Amago TsunehisaSaitō DōsanTaigen SessaiMōri MotonariFrancis XavierŌuchi YoshitakaMatsunaga Hisahide
People of the Sengoku/Azuchi-Momoyama period ・ People by period
Based on facts found in textbooks and biographies. Uncertain points are marked as such.