Nanbu Harumasa (南部春政, 1517 – 12 November 1582) also known by his Buddhist Temple name Shinryu Kenpō (俊龍拳法, Hepburn: Toshi Ryū kenpō, or “Fearless Tiger Swift Dragon”), was a pre-eminent daimyō in Sengoku Period Japan. Based in central Mutsu Province, Harumasa came to control most of the Tōhoku region by 1563, with considerable influence over the eastern Tōkaido and Tōsando regions. Renowned as an exceptional strategist and tactician, Harumasa repeatedly defeated much larger forces, establishing the Nanbu as the dominant clan in the Tōhoku region and earning himself the nickname of the “Fox of Ninohe” (二戸の狐) in reference to his cunning intellect.
Earning his first victory at the age of 20 under his father, Harumasa would come to the position of clan head in 1540. Almost immediately he was faced by a rebellion and hostile neighbours to the south, but was able to defeat both within just four years. Harumasa would also war with his aggressive western neighbour, Andō Kiyosue, from 1550 to 1555, clashing most famously at the battle of Gojōme in 1554, eventually resulting in his subjugation of the lands under Andō control.
Upon his conquest of the Daidoji, Onodera and Kasai clans, Harumasa chose to maintain good relations with the Uesugi, Ashina and Nikaidō clans although did not join the Tōhoku Alliance, possibly to avoid being pulled into wars with the Takeda and Hōjō. However, following the war between the Takeda and Ashina, Harumasa used the opportunity to push into Ashina and Nikaidō lands, seizing Fukushima and Soma. Managing to defeat Nikaidō Teruyuki at the battle of Motomiya, Harumasa continued to advance further south but was countered at the indecisive battle of Nakajima by a combined Ashina and Nikaidō army. Soon after, the three clans made peace, but with conditions that heavily favoured the more powerful Nanbu, an indication of Harumasa's greatly superior position.
Harumasa was the last major daimyō to be defeated by Urakami Munekage and is believed by some to have been considered an equal by Munekage. As such, Harumasa seemed to have gained a great deal of autonomy from the Urakami Shogunate and during the brief civil war between Munekage’s sons, the Nanbu clan remained neutral. Likely due to his mighty reputation, Takakage and the loyalist faction did not punish Harumasa for his refusal to assist them during the war, and his clan was named as “Continual Overlords of Tōhoku” (東北の絶え間ない大君主), maintaining this position until the Nōmin War, roughly three-hundred years later.
History[]
Early life[]
Harumasa was born in 1517 in Mutsu province, son of Nanbu Yasunobu, in turn the son of Nanbu Masayasu. Harumasa spent much of his early years being tutored by both his father and his uncles, Ishikawa Takanobu, Minami Nagayoshi and Kemanai Hidenori at Kunohe Castle.
Yasunobu and his younger brothers sought to increase the strength of the Nanbu clan primarily through the pacification of their rebellious northern side-branch the Ōura (later Tsugaru). They managed this by the mid-1520s, having seized a number of Ōura forts and threatening to march on Sannohe, the Ōura's seat. After achieving this, and installing Takanobu as busho of the Tsugaru region, Yasunobu turned his attention south to the Shiba Clan of Iwate. During his father's war with the Shiba, Harumasa is said to have lead a cavalry regiment in a charge at the battle of Mido. Despite the victories, Yasunobu was unable to gain the decisive victory he desired and was forced to return to Mutsu. Nonetheless, the peace treaty between the two clans dictated that the Shiba were to be considered vassals of the more powerful Nanbu, effectively making the war an overall success.
Harumasa succeeded his father in 1540, assisted by his uncle Takanobu who served as a loyal general and advisor despite his steadily declining health. Harumasa was constantly at odds with Ōura Tamehiro, the head of the side branch of the Nanbu. Despite the recent pacification of the Ōura, Tamehiro nevertheless managed to exert considerable influence upon Nanbu retainers and constantly attempted to manipulate the young Harumasa. Takanobu assisted Harumasa where he could, but both knew that Tamehiro would have to be removed at some point.
War with the Shiba[]
In 1543, Shiba Tsuneaki rebelled against the Nanbu by seizing a number of forts along the Kitakami river. Harumasa moved south with a small force and set up camp in between two hills in Shibutami. He then split his force in three, one advancing on one of the forts, one to guard the camp and the third to scale Mount Himekami for reconnaissance. Tsuneaki, upon hearing of this, rushed to take the divided forces piecemeal. Upon arrival at the fort, he discovered that the Nanbu had retreated and pursued. Seeing the flags on Mount Himekami, he assumed the scouting force was still on the mountain and attacked the camp. His force arrived at the camp exhausted and began to loot it. It was then that the three forces launched their ambush, advancing simultaneously in a three-pronged attack, cutting off Tsuneaki’s escape route.
Having defeated and captured Tsuneaki, Harumasa advanced south and besieged Kawaguchi Castle. After a short siege, the castle was seized, along with the vast majority of Iwate's hinterlands. Harumasa spent the next few weeks securing the regions around Iwate, including the construction of a series of outposts along the southern border. The young daimyō sent an offer of alliance to clans south of Iwate, including the Hienuki, Asonuma, Onodera and Kasai. Whilst the Asonuma seemed receptive to such an idea, the Onodera and Kasai were apprehensive about allying with the Nanbu, whose recent invasion of Iwate they considered overly expansionistic. Finally, pressured by their western and southern neighbours, the Hienuki allied themselves with the Onodera and Kasai in opposition to Harumasa's offer.