She was a woman trained in martial arts and received education from the highest court.

In 1583 when Yoshiuji died without a male heir, Ujihime succeeded her father at the early age of nine, she took the title Koga kubō (title equivalent to shōgun in Kantō region) and inherited an area equivalent the Koga domain.

Ujimasa was ordered to commit seppuku along with his brother Hōjō Ujiteru.

The area was awarded to Tokugawa Ieyasu after the defeat of the Hōjō at the siege of Odawara.

The clan Ujinohime founded prospered for years and became a fudai daimyo in the Edo period.