Sagoshi Ujitaka served as a bushō during the late Muromachi and Sengoku periods. He was the lord of Sagoshi Castle in the Akumi District of Dewa Province.
The Sagoshi originated as an illegitimate branch of the Daihōji clan. The Sagoshi were kokujin, or provincial landowners, serving as governors of the Akumi District.
Ujitaka was born as the son of Sagoshi Ujimasu (Yaguchi Ujimasu) who was descended from Ashikaga Ieuji from the mid-Kamakura period. Ujitaka was five generations removed from Ieuji. In 1478, in an effort to resist an expansion of the influence of the Daihōji clan in the Tagawa District of Dewa, he petitioned the Muromachi bakufu to become an official. He then received the nominal title of Shinano-no-kami, or Governor of Shinano, and a fief of 30,000 koku in the Akumi District of Dewa. Ujitaka traveled to Kyōto and met with Ashikaga Yoshihisa, the ninth shōgun of the Muromachi bakufu. This significantly bolstered his reputation.
Thereafter, in 1512, he invaded the Tagawa District and prevailed in a large-scale battle against Daihōji Sumiuji, the thirteenth head of the Daihōji clan. Between the Sagoshi and Daihōji camps, despite having lost over 1,000 soldiers, in 1513, Ujitaka decided to invade the Tagawa District again. On this occasion, however, his attack failed, his forces were defeated, and both Ujitaka and his son were killed in action.
In 1518, after the death of Ujitaka, the bloodline of the Sagoshi clan came to an end but the family was later revived by an individual who adopted the name of Sagoshi Ujifusa and was either the younger brother or son of Daihōji Masauji (a bushi and the twelfth head of the Daihōji clan) assigned to Sagoshi Castle after the demise of Ujitaka.