Mishuku Masatomo served as a bushō from the Sengoku to early Edo periods.

The Mishuku originated from the Suntō District of eastern Suruga Province.  The Mishuku were members of the Katsurayama clan, powerful kokujin, or provincial landowners in the Suntō District.  Prior to the birth of Masatomo, the Mishuku served the Imagawa, but once the Imagawa declined, the clan switched its allegiance to the Kai-Takeda of neighboring Kai Province.

In 1567, Masatomo was born as the son of Mishuku Tomotsuna, a bushō and physician to Takeda Shingen.

Masatomo served numerous lords including Takeda Shingen and Takeda Katsuyori (father and son), Hōjō Ujimasa and Hōjō Ujinao (father and son), and Tokugawa Ieyasu.  He then served Ieyasu’s second son, Yūki Hideyasu.  There is a story that Masatomo was engaged by Hideyasu for an income of 10,000 koku, but, according to several other historical records, he received either 500, 700, or 800 koku.

In 1607, after the death of Hideyasu, Masatomo served Hideyasu’s successor, Matsudaira Tadanao, but he did not get along well with him so, after 1610, he became a rōnin, or wandering samurai.

In 1614, after the beginning of the Siege of Ōsaka, he entered Ōsaka Castle for the Toyotomi and served as a deputy for Ōno Harufusa.  Upset that Masatomo was serving Harufusa, Tadanao offered a bounty of 5,000 koku to eliminate him.

During the Nighttime Attack at Honmachibashi in the Winter Campaign of the Siege of Ōsaka, Masatomo, along with Ban Naoyuki, Komeda Koresue, and others, served valorously.  According to one theory, he joined the forces assaulting Sanadamaru – an auxiliary castle constructed in defense of Ōsaka Castle.

In 1615, the Battle of Tennōji and Okayama marked the end of the Summer Campaign of the Siege of Ōsaka.  At the gateway to Tennōji, Masatomo was killed by Nomoto Ukon, a retainer of Matsudaira Tadanao.

Anecdotes

In 1615, when Tokugawa Ieyasu reviewed the list of bushō who entered Ōsaka Castle prior to the Summer Campaign of the Siege of Ōsaka, he said that among the group of rōnin, the worthy bushō were limited to Gotō Matabei and Mishuku Kanbei.

According to a compilation of stories of the Fukui domain, Nomoto Ukon and Masatomo were old acquaintances.  At the end of the Summer Campaign, Masatomo sent a messenger to Ukon on the opposing side to convey that “Although I am unworthy, I am headed into battle toward you as one of the generals defending Ōsaka Castle but I am without a horse.  Accordingly, please request Lord Matsudaira to provide his coveted horse named Aranami.”  When Ukon conveyed this message, Tadano became upset and asked “Why are you making this request?”  After Ukon settled him down, Tadanao allowed Masatomo to use his horse.  The next day, Masatomo rode Aranami into battle and was killed.

A cherished sword from Ieyasu made by Mitsuyo (Miike Tenta) a famous sword maker from Chikugo Province during the late Heian period known as the myōjun-denji sohaya-no-tsurugi utsusunari was kept by the Mishuku family for generations.

There is a story that Masatomo was the grandson of Takeda Shingen (rather than the son of Mishuku Tomotsuna, he was the son of Katsurayama Nobusada who was Shingen’s sixth son).

During his childhood, it is said that Masatomo was disowned by his father, Tomotsuna, and transferred to the Hōjō family.  After the demise of the Kai-Takeda, Masatomo and his father served the Hōjō so, if he was in fact disowned by his father, this is surmised to have occurred after the Hōjō were extinguished.  Tomotsuna and Masatomo’s younger brother, Masatsuna, were engaged in service by Yūki Hideyasu and did not remain with Masatomo.  Later, Masatsuna served Matsudaira Tadateru.

According to one theory, Masatomo served Matsuda Norihide of the Gohōjō clan, and, at the Siege of Ōsaka, as a retainer of Norihide, he would not have served as a yoriki, or security officer.  There are stories that he served Fukushima Masanori, Uesugi Kagekatsu, and Kuroda Nagamasa, but this is not substantiated.

According to compilation from a military scholar during the Edo period, Yoda Yasukatsu, Amagata Michitsuna, Nagai Yasumori, Mishuku Kanbei, Shimada Ukyō were former retainers of Ieyasu but each one of them left for assorted reasons.  After Kanbei became a rōnin, he was invited and assigned a role by Hideyasu.  Hideyasu noted “Even if Kanbei had betrayed the Tokugawa family, as long as he had not violated the customs of the bushi, then I invited him to join and to serve without changing his surname.”