At first, they called themselves Tochi no obito (with 'obito' being "kabane," or hereditary title), but the Nakahara clan was established when Usho TOCHI (十市有象) and Ichu TOCHI (十市以忠) changed their name to Nakahara no sukune (with 'sukune' being newly introduced kabane) in 971 and was bestowed with "asomi" (higher kabane than sukune) in 974, thus becoming Nakahara no asomi.
はじめは十市氏首(姓)であったが、971年に十市有象・十市以忠が中原宿禰姓に改め、974年に中原朝臣姓を賜ったことに始まった。