was a chieftain of the Taira clan in the early 11th century, and predecessor of the Chiba clan. He was also, for a time, Governor of Shimōsa and Vice-Governor of Kazusa Provinces, and manager of the Grand Shrine of Ise in fact if not in name. Knowing he could not defeat Yorinobu, Tadatsune surrendered without a fight, and was taken prisoner, perishing on the way to the capital.