Yoshikazu was an adopted son of Minamoto no Yoritomo's wetnurse, and elder brother to Tango no tsubone (mother of Shimazu Tadahisa). When Yoritomo called his banners, Yoshikazu took part in traveling to the western provinces to help fight the Taira clan. Yoshikazu was a close and loyal retainer to Yoritomo, and married his daughter Wakasa no tsubone to Yoritomo's son Minamoto no Yoriie.
Following Yoritomo's death, the Hôjô attempted to lessen the Hiki clan's power. Angered by this, Yoshikazu led an uprising against Hôjô Tokimasa in 1203, with the support of Yoriie. This ended, however, in Yoshikazu's death, and in the destruction of the Hiki clan, as they were hunted down by Tokimasa's men.
Yoshikazu's son Hiki Yoshimoto survived, however, and established a small meditation hall on the grounds of Yoshikazu's Kamakura mansion; this hall later developed into the Buddhist temple Myôhon-ji, which survives today. Yoshikazu's second son, meanwhile, was the monk Giasessei shônin, who founded the temple of Jôkômyô-ji in Kagoshima.
- Plaques on-site.; "Myôhon-ji." Kamakura-burabura.com.
- Miyagi Eishô 宮城栄昌, Ryûkyû shisha no Edo nobori 琉球使者の江戸上り, Tokyo: Daiichi Shobô (1982), 80-81.