Minamoto no Yoshiie
The was a family of Japanese people descended from the Seiwa Genji. Their line descended from Minamoto no Yoshiie (also known as Hachimantaro) through his seventh son, Minamoto no Yoshitaka, proprietor of Mōri-no-shō in Sagami Province. His son, Minamoto no Yoritaka, took Mori as his surname when he retired, and Yoritaka's son Yorisada continued to use the surname.