Haryū Moriyuki served as a bushō during the Sengoku period.  Moriyuki was born as the son of Ashina Morishige, the fourteenth head of the Ashina clan of Mutsu Province.   His son was Haryū Moriaki.

After Morishige retired, he did not have a son, so he transferred headship of the clan to his younger brother, Ashina Morikiyo.  However, during Morishige’s retirement, Moriyuki was born.

Morikiyo’s lineage inherited the headship of the Ashina clan for generations, so Moriyuki did not inherit the clan.

Moriyuki held land in Haryū in the Yama District of Mutsu so he changed his surname to Haryū and founded a new family.

Although Moriyuki did not become the head of the Ashina clan, following the demise of Ashina Sentsurumaru in 1653 of the Edo period, the lineage of the Ashina clan came to an end, so descendants who served as retainers of the Date clan revived the Ashina clan.