In July 1124, TAIRA no Tsuneshige (hereinafter "Tsuneshige CHIBA"), who was a founder of the Chiba clan, was adopted by his uncle Goro SOMA, TAIRA no Tsuneharu and given the Soma county, Shimosa Province, and in November 1124, he became Soma gunji (district managers of the Soma county).
天治元年（1124年）6月、千葉氏の祖である平常重（以下千葉常重）は叔父・相馬五郎平常晴の養子とされ、相馬郡(下総国)を譲られて、10月には相馬郡司となった。