was a samurai

Samurai

is the term for the military nobility of pre-industrial Japan. According to translator William Scott Wilson: "In Chinese, the character 侍 was originally a verb meaning to wait upon or accompany a person in the upper ranks of society, and this is also true of the original term in Japanese, saburau...

 and Imperial Prince during Japan's Heian period

Heian period

The is the last division of classical Japanese history, running from 794 to 1185. The period is named after the capital city of Heian-kyō, or modern Kyōto. It is the period in Japanese history when Buddhism, Taoism and other Chinese influences were at their height...

, the progenitor of the Seiwa Genji

Seiwa Genji

The ' were the most successful and powerful of the many branch families of the Japanese Minamoto clan. Many of the most famous Minamoto warriors, including Minamoto Yoshiie, also known as "Hachimantaro", or God of War, and Minamoto no Yoritomo, the founder of the Kamakura shogunate, were descended...

 branch of the Minamoto clan

Minamoto clan

was one of the surnames bestowed by the Emperors of Japan upon members of the imperial family who were demoted into the ranks of the nobility. The practice was most prevalent during the Heian Period , although its last occurrence was during the Sengoku Era. The Taira were another such offshoot of...

. He was the son of Sadazumi-shinnō and grandson of Emperor Seiwa

Emperor Seiwa

was the 56th emperor of Japan, according to the traditional order of succession.Seiwa's reign spanned the years from 858 through 876.-Traditional narrative:...

.

Tsunemoto took part in a number of campaigns for the Imperial Court, including those against Taira no Masakado

Taira no Masakado

was a samurai in the Heian period of Japan, who led one of the largest insurgent forces in the period against the central government of Kyoto.-History:...

 in 940 and against Fujiwara no Sumitomo

Fujiwara no Sumitomo

was a Japanese Heian era court noble and warrior. From 939 to 941 he aided the Taira clan in a series of revolts.Sumitomo built his power base in Northern Kyushu. After making a secret agreement with Taira no Masakado, who was leading a revolt in Shimōsa Province, Sumitomo led his own revolt in Iyo...

 the following year.

He held the title of Chinjufu-shogun, or Commander-in-chief of the Defense of the North, and was granted the clan name of Minamoto by the Emperor in 961, the year he died.

Tsunemoto was the father of Minamoto no Mitsunaka

Minamoto no Mitsunaka

, son of Minamoto no Tsunemoto, was a samurai and Court official of Japan's Heian period. Mitsunaka belonged to the Seiwa Genji branch of the Minamoto clan, which traced its ancestry to Emperor Seiwa. He loyally served several successive Fujiwara regents beginning with Fujiwara no Morotada...

.