He succeeded his father as head of the Shimazu clan, and as jitô and shugo of Satsuma, in 1227, but continued to serve the shogunate loyally until his death in 1272. Tadatoki had three sons. His eldest son, Shimazu Hisatsune, succeeded him in 1272. Of his other two sons, Shimazu Tadatsugu became the founder of the Yamada clan, and Shimazu Tadatsune became the ancestor of the Ijûin and Machida clans.
|Head of Shimazu clan & jitô-shugo of Satsuma province