The First Siege of Takatenjin Castle occurred in the fifth and sixth months of Tenshō 2 (1574) in Hijikata in the Kitō District of Tōtōmi Province.  This conflict was waged between Takeda Katsuyori (a sengoku daimyō and the seventeenth head of the Kai-Takeda clan) and Tokugawa Ieyasu (a sengoku daimyō and, later, the supreme shōgun of the Edo period).  This was followed, in 1581, by the Second Siege of Takatenjin Castle between the same lords and their clans.

Background

Originally, Takatenjin Castle was an auxiliary site of the Imagawa clan located near the provincial borders of Tōtōmi and Suruga.  Ogasawara Ujioki served as its lord.  Owing to the decline and eventual decimation of the Imagawa beginning with their defeat to the Oda at the Battle of Okehazama in 1560 until the Invasion of Suruga in 1568 by the Kai-Takeda, Ujioki submitted to the Tokugawa clan.  From the perspective of the Tokugawa, Takatenjin stood in a critical location for the governance of Tōtōmi.

After the pacification of Suruga, the Takeda clan began to extend its reach in the direction of Mikawa and Tōtōmi provinces, leading to skirmishes with Tokugawa forces.  In 1571, Takeda Shingen led a formidable army of 25,000 soldiers to invade Mikawa and Tōtōmi.  On this occasion, the Tokugawa attacked Takatenjin Castle but withdrew the same day.  In 1572, during an invasion of Tōtōmi by the Kai-Takeda known as the Western Campaign, Futamata Castle, a vital location situated in-between Takatenjin Castle and the main base of the Tokugawa clan at Hamamatsu Castle, was toppled.  This is known as the Siege of Futamata Castle.  As a result, Takatenjin Castle became isolated.  At this time, however, Takatenjin Castle was not yet serving as a base for the Tokugawa clan.

After the death of Shingen in the fourth month of 1573, his successor, Takeda Katsuyori, aimed to capture Takatenjin Castle as a means to strengthen the governance of Tōtōmi.  Consequently, the Takeda and Tokugawa clans battled for control of Takatenjin Castle as a base from which to exert their influence in Tōtōmi.

Prelude

On 4/12 of Genki 4/Tenshō 1 (1573), Takeda Shingen died in Komaba in the Ina District of Shinano Province while returning to Kōfu on the Iida Road in the wake of the Western Campaign.  Initially, the Takeda concealed his death while his son, Katsuyori, succeeded him as the next head of the Kai-Takeda.  While the Kai-Takeda organized a new command structure, Oda Nobunaga counterattacked.  On 7/18, upon expelling Ashikaga Yoshiaki, the fifteenth and final shōgun of the Muromachi bakufu, from the capital of Kyōto, Nobunaga influenced the Imperial Court to commence a new era – Tenshō.  In the eighth month, the Oda army eliminated Asakura Yoshikage of Echizen Province followed by Azai Nagamasa (Nobunaga’s younger brother-in-law) of Ōmi Province.

Meanwhile, Tokugawa Ieyasu (who maintained an alliance with the Oda clan) exploited the death of Shingen to launch counterattacks to recover territory earlier lost in Mikawa such as by recapturing Nagashino Castle (in the Shitara District) and luring Okudaira Sadayoshi, the lord of Tsukude-Kameyama Castle, to betray the Takeda in favor of the Tokugawa.

Course of events

In 1573, to gain a foothold for the capture of Takatenjin Castle, Takeda Katsuyori dispatched Baba Nobuharu (Nobufusa) to Tōtōmi to commence the construction of Suwahara Castle.  The Tokugawa clan, possessing less military might than the Takeda, tacitly permitted this activity.

In the fifth month of 1574, the Takeda clan mobilized 25,000 men and, via Oyama Castle in the Haibara District, attacked the base of the Tokugawa at Takatenjin Castle in the eastern portion of Tōtōmi.  The castle was defended by Ogasawara Nagatada with a garrison of less than 1,000 soldiers in the Tokugawa army.  While defended against the assault by the Takeda forces, the Ogasawara appealed to the Tokugawa family for support.  The defenders needed to prepare for the possibility of a detached division of the Takeda army coming south from Shinshū (Shinano Province).  Moreover, the total forces of the Tokugawa family were limited to 10,000 men so Tokugawa Ieyasu turned to Oda Nobunaga to request reinforcements.

On 5/5, Nobunaga attended the Kamo Festival at the Kamo-Mioya Shrine in Kyōto but, after ordering the imposition of taxes in his territory, on 5/16, departed from the capital.  On 5/28, he returned to his base in Gifu.  During this time, the western citadel of Takatenjin Castle fell in an assault by the Takeda army and provisions ran low, making the fall of the castle an imminent threat.

On 6/14, a reinforcement army under Nobunaga departed from Gifu, arriving on 6/17 at Yoshida Castle in the Atsumi District of Mikawa.  On 6/18, a kunishū, or provincial landowner, Ogasawara Ujisuke (Nobuoki) who was based at Takatenjin Castle colluded with Katsuyori and launched a revolt from within the castle against Nagatada, forcing his surrender.

In this manner, Takatenjin Castle is deemed to have been occupied.  In the authenticated biography of Oda Nobunaga known as the Shinchō kōki, the individual identified as Ogasawara Ujisuke or Ogasawara Nagatada is the same individual as Ogasawara Nobuoki.  This gives rise to inconsistencies in the accounts regarding the course of events leading to the capture of the castle by the Takeda as described above. 

The account premised upon Ogasawara Nobuoki being the commander of the castle (and the same individual as Ogasawara Nagatada) is as follows:

Nobuoki, along with other bushō, holed-up in the castle but after making repeated urgent requests from the fifth month for reinforcements, there were no signs of a response from Ieyasu.  During a siege that ran for approximately sixty days, the Takeda forces breached several baileys while Honma Ujikiyo, Maruo Yoshikiyo, and Takanashi Hidemasa were all killed in the course of the battles.  Only the bailey surrounding the keep remained in the hands of the defenders.  As a result, Nobuoki agreed to vacate the castle in exchange for having spared the lives of his soldiers.

After the castle was turned over to the besieging forces, Takeda Katsuyori took lenient steps.  He did not punish anyone and spared the lives of all of the defenders.  He did not restrain them and, further, allowed those bushō seeking to surrender to the Takeda to join their ranks, including Watanabe Nobushige, Date Yohei (Muneharu), Fushiki Hisauchi, Nakayama Zehinosuke, Yoshihara Matabei, Hayashi Heiroku, and Matsushita Norihisa.  Others, including Ōsuga Yasutaka, Atsumi Katsuyoshi, Sakabe Hirokatsu, Kuze Hironobu, and Monna Toshitake were permitted to return to the territory of the Tokugawa family.  The bushō who joined the Takeda served under the command of the Ogasawara in the Battle of Anegawa.  These men accounted for six of the seven bushō recognized for the valor and known collectively as the Seven Spears of Anegawa, indicating that they had cut ties with the Tokugawa family.  Ogasawara Nobuoki also severed ties to the Tokugawa and surrendered to the Takeda.  He was transferred to the eastern portion of Suruga with a liberal compensation of 10,000 kan.  Matsushita Yukitsuna was also released.  At the time, Toyotomi Hideyoshi served as a retainer of Oda Nobunaga and as lord of Nagahama Castle.  Hideyoshi invited Yukitsuna to become one of his retainers, becoming a daimyō with a fief of 16,000 koku.  In 1575, Yukitsuna led a troop of 100 soldiers in front of Hideyoshi at the Battle of Nagashino.

Following the capture of the castle, the adoption of generous measures by Katsuyori boosted his reputation.  By contrast, the failure by the Oda and Tokugawa to dispatch reinforcements in time caused harm to their image.

On 5/18, after Nobunaga received news that the castle had fallen while en route with reinforcements, Ieyasu came from Hamamatsu to convey his thanks.  As payment for provisions, Nobunaga gave gold pieces to Ieyasu.  He gave two leather bags filled with gold that required two men to lift and mount on a horse.  On 6/21, Nobunaga returned to Gifu.

After Ōsuga Yasutaka returned to Hamamatsu, he was immediately assigned to Mamushizuka Castle located on the front lines opposing Takatenjin Castle.  Other bushō including Atsumi Katsuyoshi, Sakabe Hirokatsu, and Kuze Hironobu who returned in the same unit as Yasutaka were assigned as yoriki, or security officials.  These men were referred to as members of the Yokosuka Group or Yokosuka Group of Seven associated with Yokosuka Castle built by Yasutaka in 1578 in the Kitō District of Tōtōmi.

The Takeda renovated the fallen castle while stationing Okabe Motonobu, a former retainer of the Imagawa clan, to serve as the commander of the castle.