Ariwara family

Ariwara clan 在原氏
Parent house	Imperial family
Founding year	Kōnin (810-824)

The Ariwara clan (在原氏, Ariwara-uji, also known as the Arihara clan) was a Japanese noble family of imperial descent

The name of the clan is also read Arihara.

The clan was initially formed during the Kōnin era (810-824) in the reign of Emperor Saga from the children of former Imperial Prince Takaoka (廃太子高岳親王, hai-taishi Takaoka-shinnō). In 826, following a request by Takaoka's brother Prince Abo (阿保親王, Abo-shinnō), the latter's sons Yukihira, Narihira, Morihira (守平) and Nakahira (仲平) were also given this name. The descendants of Narihira, a great waka poet, continued to flourish. The clan remained politically obscure, however, due to pressure from the powerful Fujiwara clan.

...
Wikipedia