Okumura Nagatomi served as a bushō from the Sengoku to early Edo periods.  He was a retainer of the Maeda clan.

In 1541, Nagatomi was born in Nakashima-no-kōri in Owari Province.  For generations, the Okumura clan served the Maeda clan.  Nagatomi first served Maeda Toshiharu (the father of Maeda Toshiie) and Toshiie’s older brother, Maeda Toshihisa.  In 1569, upon the death of Toshiharu, Toshihisa, in his role as the eldest son, inherited the headship of the Maeda family.  Oda Nobunaga, however, suddenly ordered Toshiie (in lieu of Toshihisa) to lead the Maeda family.  This owed to the fact that Toshihisa lacked a natural heir and was of frail health.  At this time, while serving as the chamberlain of Arako Castle in Owari, Nagatomi refused to vacate the castle unless ordered by Toshihisa to do so.  Upon subsequent orders from Toshihisa to vacate, he resigned from the Maeda family and became a rōnin, or wandering samurai.

In 1573, after the Oda army invaded Echizen Province, Nagatomi returned to the Maeda family.  Nagatomi followed Toshiie who served as a yoriki, or security officer, for Shibata Katsuie.  Nagatomi joined in battles against the Asakura across Echizen.  Later, after Toshiie entered Kaga Province, Nagatomi was awarded Suemori Castle.  In 1584, when his lord, Toshiie, affiliated with Hashiba Hideyoshi (later known as Toyotomi Hideyoshi), Nagatomi incurred an attack at Suemori Castle by an army of 15,000 soldiers led by Sassa Narimasa of Etchū Province.  Despite a breach of the outer citadel by the attackers, Nagatomi, together with a garrison of 300 soldiers, held-out until the arrival of reinforcements from Toshiie, repelling the Sassa forces in an event known as the Siege of Suemori Castle.  During the battle, Nagatomi’s wife, Tsune, walked around the castle holding a naginata, or glaive, distributing watery cooked rice and attending to the injured soldiers, raising their spirits.

Thereafter, Nagatomi, along with Murai Nagayori, built the foundation of the Kaga-Maeda domain.  Although the timing is uncertain, he was conferred the Toyotomi surname.  Nagatomi participated in the Subjugation of Kyūshū and the Conquest of Odawara.  During the Siege of Ōsaka, he served as the chamberlain of Kanazawa Castle.  Following the death of Toshiie, Nagatomi retired and entered the priesthood.  Later, upon request of Maeda Toshinaga, he returned to service and, under Maeda Toshitsune, served as the head of the elders.  In 1611, for reasons of old age, he retired again.  Toshitsune was the younger brother of Toshinaga who was adopted by Toshinaga to be his successor and, in 1605, became the second lord of the domain following the retirement of Toshinaga.

In 1624, Nagatomi died at the age of eighty-four.  His grave and portrait are at the Nagatomi Temple in the city of Kanazawa in Ishikawa Prefecture.  Among the Eight Families of the Maeda, his descendants led two of them, serving for generations as chief retainers of the Maeda.  At the end of the Edo period, his descendants passed-down the name of Okumura Suke-emon.

His third son, Okumura Haruyori, was deeply trusted by Maeda Toshitsune but lost his reputation after being defeated by Sanada Nobushige at the Winter Campaign of the Siege of Ōsaka.  Haruyori was also dissatisfied with the return to service of Yokoyama Nagatomo, a political enemy who had earlier been forced to flee, so he left the Kaga domain.  Thereafter, other retainers of the Maeda representing landholdings of over 10,000 koku including Haruyori’s older brothers as well as Honda Masashige (with whom Haruyori had friendly relations) attempted to leave the domain.  Nagatomi convinced them to stay so that, in the end, only Haruyori left and he put a halt to the disturbance within the family.