"[3] Despite being vastly outnumbered, the Hōjō army defeated the besiegers because, under Ujiyasu's orders, they were not bulked down by heavy armor and were not slowed by seeking to take heads.

In 1561, after Uesugi withdrew from Odawara, the Hojo clan seized Iwatsuki Castle against Ōta Sukemasa and almost conquered whole Musashi Province.

[4] In 1563, Ujiyasu allied himself with Takeda Shingen and regained Matsuyama Castle (松山城)[6] in Musashi Province against Uesugi Norikatsu (上杉憲勝) (Siege of Musashi-Matsuyama (1563)).

Ujiyasu expanded the Hōjō territory, which now covered five provinces (Sagami, Izu, Musashi, Shimosa and Kazusa), and managed and maintained what his father and grandfather had held.

After the second battle of Konodai in 1564, the Hōjō largely contented themselves with ruling the vast tracts of land earned through 60 years of war and toil.

Towards the end of his life Ujiyasu saw the first major conflicts between his own clan and Takeda Shingen (武田 信玄), who would become one of the greatest warlords of the period.

As the forces of Shingen withdrew from repeated failed sieges of Odawara Castle, two of Ujiyasu's seven sons, the brothers Ujiteru and Ujikuni, attacked him in the pass of Mimase (Battle of Mimasetoge), ending the first of the Takeda campaigns against the Hōjō at Sagami province.

Ujiyasu died in 1571, passing on the Hōjō domains to his eldest son Ujimasa (北条 氏政) in a relatively favourable situation.