Lifespan: Unknown to 5/3 of Tenshō 4 (1576)
Title: Governor of Bitchū
Role: Military Governor of Yamashiro (southern portion) and Yamato
Lord: Oda Nobunaga
Siblings: Naoko (younger sister – consort of Oda Nobunaga – mother of Oda Nobumasa)
Wife: Daughter of Shibata Katsuie
Ban Naomasa served as a bushō and retainer of the Oda clan of Owari Province during the Azuchi-Momoyama period. Naomasa was the lord of Ōnogi Castle in the Kasugai District of Owari.
Born in the Kasugai District of Owari, Naomasa first served as an umamawari, or mounted soldier, for Oda Nobunaga. He was selected as a member of the elite group of soldiers who rode with a red horo, a cape that would inflate behind the riders to serve as protection against stones or arrows shot at them in battle. Naomasa accompanied Nobunaga during his move to Gifu Castle and resided in the castle.
In 1568, after Nobunaga entered Kyōto, he served as the official in charge of administrative affairs in the Kinai. Upon his appointment as a bugyō, or magistrate, for which he acted in the role of an auditor, Naomasa was bestowed with ranjatai, a special type of fragrant wood stored at the Tōdai Temple in Nara. In the fifth month of 1574, he was assigned as the military governor for the southern portion of Yamashiro Province. In the third month of 1575, he added to his duties the role of military governor for Yamato Province. Naomasa served meritoriously in numerous battles, including the campaign against adherents of the Ishiyama-Hongan Temple, the Invasion of Ise-Nagashima, the Siege of Takaya Castle, and the subjugation of riots by followers of the Ikkō sect in Echizen Province in 1575 in an event known as the Echizen Ikkō-ikki. Together with Hashiba Hideyoshi, Akechi Mitsuhide, and Yanada Hiromasa, Naomasa was conferred with honors and appointed the Governor of Bitchū and the surname of Harada, a powerful family in Kyūshū. In addition to governing Yamato and the southern portion of Yamashiro, the Oda forces removed auxiliary castles in Kawachi Province, solidifying Naomasa’s control over the majority of three provinces. At its peak, Naomasa’s influence was on a par with the class of veteran retainers of the Oda such as Shibata Katsuie.
In the fifth month of 1575, at the Battle of Nagashino, Naomasa was appointed as an infantry commander, along with senior retainers including Sassa Narimasa, Maeda Toshiie, Nonomura Masanari, and Fukuzumi Hidekatsu.
In the fourth month of 1576, Naomasa joined Akechi Mitsuhide, Araki Murashige, Hosokawa Fujitaka, and Miyoshi Yasunaga in deploying for the campaign against the Ishiyama-Hongan Temple. Naomasa led the main contingent in an attack against the Mitsu Temple in the west, but was killed after encountering forces fighting on behalf of the Hongan Temple. The opponents were members of the saikashū led by Suzuki Shigehide. Hailing from the northwestern portion of Kii Province, the saikashū were an incongruous band of arquebusiers and swordsmen comprised of mercenaries and provincial samurai who tended fields outside of their battlefield pursuits. This loss resulted in a break in the front lines, posing a danger to the Oda forces, but through intense fighting led by Nobunaga himself, the Oda succeeded in reclaiming the line in the Battle of Tennō Temple. In addition to Naomasa, family members including, among others, his uncle (Ban Yasuhiro) and younger brother (Koshiirō), perished in the battle. Having lost many of their bushō in the conflict, Nobunaga held the Ban family responsible for the outcome and the clan was extinguished. Ban Naoyuki, who later died in the Winter Campaign of the Siege of Ōsaka waged from 1614 to 1615, may have been related to Naomasa, but it is not certain.