Matsudaira Nagachika served as a bushō during the Sengoku period.  Nagachika was the great-great grandfather of Tokugawa Ieyasu.

Nagachika was born as the third son of Matsudaira Chikatada, the fourth head of the Matsudaira clan.

In 1496, following the retirement of Chikatada, Nagachika became the second head of the Anjō-Matsudaira family and lord of Anjō Castle.  Around this time, he incurred an attack by Imagawa Ujichika of neighboring Suruga Province, placing Nagachika in a precarious situation.  Nagachika also fought against Ise Moritoki (later known as Hōjō Sōun), a retainer of Ujichika.  As a resourceful bushō, Nagachika successfully defended against the attack by the Imagawa.  In addition to his military prowess, Nagachika excelled in renga, or linked-verse poetry.  He is regarded as the figure who built the foundation enabling the rise of the Matsudaira clan from kokujin, or provincial landowners, in Mikawa to sengoku daimyō.

Decimation of the Iwatsu-Matsudaira family by the Imagawa army

In the eighth month of 1508, the Imagawa army led by Ise Sōzui (as a proxy for Imagawa Ujichika) established a main base at the Daiju Temple and attacked Iwatsu Castle.  This was one chapter in a series of events known as the Eishō Mikawa Conflict.  According to accounts written by Ōkubo Tadataka, a bushō who lived from the Sengoku to early Edo periods, the lord of Iwatsu and renowned retainers maintained their composure, acting so as not to draw the enemy to the castle and leaving the Imagawa forces uncertain how to respond.  After Nagachika from Anjō Castle appeared in Idano with reinforcements to head toward Iwatsu, the Imagawa sought to intercept them, but these forces struggled against Nagachika, allowing Nagachika and his men to approach the main base of Ise Sōzui.  Fearing an attack from the rear by the Toda clan, the Imagawa army retreated.  Under another theory, the Imagawa withdrew given that the primary target of the attack was the Iwatsu-Matsudaira family.

The outcome of this battle is deemed to have led to the rapid decline of the Iwatsu-Matsudaira family, and, as a result, the Anjō-Matsudaira family of Nagachika is surmised to have become the lead family in the clan.

That same year, Nagachika transferred headship of the clan to his eldest son, Matsudaira Nobutada, and retired.  Retirement at this time is regarded to have been too early, but the facts are uncertain.  Nagachika may not have known his eldest son, Nobutada, was incapable to serve as the leader or, as of 1501, Nagachika may have already entered the priesthood.  Nevertheless, he continued fighting against the Imagawa army as a guardian of Nobutada and Nobutada’s lineal heir, Matsudaira Kiyoyasu.

Succession struggle 

After his retirement, Nagachika entered the priesthood, adopting the monk’s name of Dōetsu.  He continued to serve as a guardian and deputy to Nobutada, but Nobutada was inept and lacked the trust of family members and the band of retainers while the Matsudaira confronted the threat of disintegration.  As a result, upon the appeal of Sakai Tadanao (a chief retainer) Dōetsu and Nobutada accepted a plan for Nobutada’s retirement and succession by his lineal heir, Kiyoyasu.

In later years, his sons established cadet families including the Fukama-Matsudaira, the Sakurai-Matsudaira, the Tōjō-Matsudaira, and the Fuii-Matsudaira.  Among these sons, Nagachika particularly favored Matsudaira Nobusada of the Sakurai-Matsudaira.  In the twelfth month of 1535, in an event known as the Collapse at Moriyama, Nagachika’s eldest son, Kiyoyasu, was unexpectedly killed by a retainer.  Kiyoyasu’s son, Hirotada, succeeded his father at an early age and was subsequently ousted from Okazaki Castle by Nobusada.  Nagachika, however, did not take any action against Nobusada, disappointing the band of retainers.

Later, Nagachika reconciled with Hirotada, and ordered that Hirotada’s lineal heir (Nagachika’s great-great grandson) receive the childhood name of Takechiyo (similar to Nagachika, Nobutada, and Kiyoyasu).  He later became Tokugawa Ieyasu.  Meanwhile, until the era of Hirotada, Nobusada, who was favored by Nagachika, persisted in his efforts to claim the headship of the Matsudaira clan.  This caused conflicts among members of the family and their retainers and was an indirect reason for the struggles endured by Ieyasu as a youth.

On 8/22 of Tenbun 13 (1544), Nagachika died at the age of seventy-two.