Lifespan: Tenshō 10 (1582) to 5/7 of Keichō 20 (1615)
Other Names: Naiki (common)
Rank: bushō, daimyō
Title: Junior Fifth Rank (Lower), Governor of Izumo
Domain: Second lord of Kazusa-Ōtaki
Lord: Tokugawa Ieyasu
Father: Honda Tadakatsu
Mother: Kenseiin (daughter of Awachi Gentetsu)
Siblings: Komatsuhime (wife of Sanada Nobuyuki), Morihime (wife of Okudaira Iemasa), Tadamasa, Tadatomo
Wife: Daughter of Hitosuyanagi Naomori
Children: Masakatsu, Chiyo (formal wife of Honda Masatomo), daughter (wife of a member of the Yamaguchi clan), Izumo-no-kami
Honda Tadatomo served as a bushō and daimyō during the Azuchi-Momoyama and early Edo periods. He was the second lord of the Ōtaki domain in Kazusa Province.
In 1582, Tadatomo was born as the second son of Honda Tadakatsu, a senior retainer of Tokugawa Ieyasu. Sharing the warrior ethos of his father, in 1600, Tadatomo joined Tadakatsu by serving in the Battle of Sekigahara. After the war, owing to his valorous service, his father was transferred to the Kuwana domain in Ise Province while Tadatomo was awarded the former fief of Tadakatsu comprised of 50,000 koku in Ōtaki in Kazusa.
In 1609, a noble from Spain named Rodrigo de Vivero y Aberruza and his party experienced a shipwreck aboard a Spanish galleon named the San Francisco which led to the drowning of over 50 passengers while over 300 survivors landed on the shore in Tajiri in the village of Iwata in Kazusa. During this incident, Tadatomo welcomed and protected those in the landing party. In his account, de Vivero noted that the party resided in this location for approximately 40 days, and, during this time, the villagers responded to their needs with devotion. Tadatomo led over 300 retainers to visit de Vivero, promised to give a report to the bakufu, and treated them with kindness.
Tadatomo fostered the cultivation of new farmlands. This included, specifically, Kuniyoshihara in 1609 and Makihara in 1611.
In 1610, prior to the death, Tadakatsu sought per his written will to transfer to Tadatomo 15,000 ryō for military expenses, but Tadatomo refused on the grounds that his older brother, Tadamasa, was responsible for large landholdings and had many uses for the funds. Meanwhile, Tadamasa said they cannot ignore the will of his father so neither of the sons attempted to receive the funds. In the end, the two of them shared the inheritance.
In 1614, after Satomi Tadayoshi of Awa Province was removed from his position, Tadatomo joined Naitō Masanaga, the lord of Sanuki Castle to demolish Tateyama Castle and surrounding fortresses.
In 1614, Tadatomo participated in the Winter Campaign of the Siege of Ōsaka, but, after drinking alcohol, lost consciousness and defeated in the face of a violent assault by the enemy forces. After being criticized by Ieyasu, in 1615, during the Summer Campaign of the Siege of Ōsaka, served in the vanguard with the aim of restoring his honor at the Battle of Tennōji-Okayama. His battalion launched a frontal assault against the army of Mōri Katsunaga and, after valiant fighting, he died on the battlefield. Tadatomo was thirty-four years old. While on the verge of death, Tadatomo said that he wanted to save those who struggled with drinking. After dying, he was worshiped as the god to block alcohol.
Tadatomo’s memorial is in the main hall at the Isshin Temple in Ōsaka. Later, his ashes were divided and interred at the Ryōshin Temple.
Mournful of the loss of Tadatomo, Ieyasu assigned Tadatomo’s orphan, Honda Masakatsu, to serve as the lord of the Kōriyama domain in Yamato Province.