Lifespan: Kōji 1 (1555) to 8/1 of Keichō 5 (1600)
Other Names: Matahachirō, Tonomonosuke (comnon)
Rank: bushō, daimyō
Lord: Tokugawa Ieyasu
Father: Matsudaira Koretada
Mother: Daughter of Udono Nagamochi
Siblings: Ietada, Tadakatsu, Korenaga, Harushige, Shōi, Chiiha (wife of Matsudaira Jintarō Ietada and, later, Atobe Masakatsu), Osachi (wife of Udono Yasutaka and, later, Matsudaira Iekiyo), Banshōin (wife of Toda Takatsugu), Oichi (wife of Matsudaira Motokatsu)
Wife: Second daughter of Mizuno Tadawake
Children: Tadatoshi, Tadasada, Tadakazu, Tadashige, Tadataka
Matsudaira Ietada served as a bushō and daimyō during the Sengoku and Azuchi-Momoyama periods. He was a retainer of the Tokugawa clan. Ietada served as the fourth head of the Fukōzu-Matsudaira family – a branch of the Matsudaira clan founded by Matsudaira Tadasada.
The diary written by Ietada entitled Ietada’s Diary is regarded as a valuable historical account to understand the lives of Sengoku bushō and powerful daimyō of that period.
In 1555, Ietada was born as the eldest son of Matsudaira Koretada (the third head of the Fukōzu-Matsudaira) and the daughter of Udono Nagamochi. He was born at Fukōzu Castle which served as the primary residence of the family located in the Nukata District of Mikawa Province. Around the time of Ietada’s coming-of-age ceremony, the Fukōzu-Matsudaira affiliated with Tokugawa Ieyasu of the main branch of the Matsudaira clan and came under the command of Sakai Tadatsugu (the chamberlain of Yoshida Castle) who was assigned governance by Ieyasu of eastern Mikawa. In the fifth month of 1575, Ietada joined his father, Koretada, to serve in the Battle of Nagashino, participating in an attack on Mount Tobisu led by Tadatsugu. After the death in battle of Koretada, Ietada inherited the headship of the family at the age of twenty-one, becoming the fourth head of the Fukōzu-Matsudaira. Although the timing is uncertain, around 1573, Ietada wed the second daughter of Mizuno Tadawake, the younger brother of Mizuno Nobumoto, the lord of Kariya Castle.
Thereafter, Ietada served in numerous battles, but, more so than the battles, he was actively involved in the construction and renovation of castles including Hamamatsu Castle, Makino Castle (Suwahara Castle), Shinshiro Castle, Yokosuka Castle, and auxiliary castles (forward operating bases) for the assault on Takatenjin Castle. This work suggests his abilities in the field of engineering. During this period, the Kōta River in their territory frequently overflowed, and references in his diary to restoration work further suggest that he cultivated his skills through these activities.
In 1590, after Tokugawa Ieyasu was transferred to the Kantō, Ietada was granted a fief of 10,000 koku in the Saitama District of Musashi Province, whereupon he made his base at Oshi Castle. Originally, Oshi and a fief of 100,000 koku were granted to Ieyasu’s fourth son, Tokugawa Tadayoshi, but at the time he was still immature so, until he reached adulthood, Ietada managed the landholdings. Later, after Tadayoshi formally became the lord of Oshi Castle, Ietada was moved to Omigawa in Shimōsa Province and resided at Kamidai Castle. Around 1592, he changed his common name from Matahachirō to Tonomonosuke.
In 1600, upon orders of Ieyasu, Ietada, along with Torii Mototada and Naitō Ienaga, guarded Fushimi Castle in the environs of Kyōto, inviting a rebellion by the Western Army led by Ishida Mitsunari. After, as expected, Mitsunari raised arms, Ietada and the others were killed in action at the Siege of Fushimi Castle – a preliminary clash to the Battle of Sekigahara between the Eastern Army led by Ieyasu and the Western Army led by Mitsunari. Fushimi Castle fell. Ietada was forty-six years old.
Ietada is known as the author of a chronicle entitled “Ietada’s Diary.” From 1575 until the tenth month of 1594, spanning a period of seventeen years, the diary is comprised of succinct entries regarding daily events. The original copy was restored by Matsudaira Tadafusa, a lineal grandson and head of the Fukōzu-Matsudaira in the early Edo period. This original work exists today. The entries range from matter-of-fact descriptions of weather and the seasons to notes in regard to political affairs, diplomacy, and battles. There are, however, few personal observations or assessments in regard to the subject of his entries except for his appreciation of nō drama and enjoyment of renga, or linked-verse poetry, and the tea ceremony, highlighting his interest in the cultural arts.
In the transition from the Oda administration to the Toyotomi administration, Ieyasu controlled five eastern provinces, establishing his own base of power. Ietada’s Diary provides insight into the Sengoku and Azuchi-Momoyama period with a focus on Ieyasu in addition to the actions of daimyō families engaged in diplomacy or antagonistic relations with the Tokugawa including the Takeda of Kai Province and the Gohōjō of Sagami Province. Entries regarding mundane matters further shed light on the daily life and customs of daimyō and military families. For example, in regard to an African named Yasuke (who originated from East Africa and came to Japan with the Portuguese missionaries and served as a retainer of Oda Nobunaga), Ietada noted that he saw him during the return of forces from the Conquest of Kōshū, stating that “His name is Yasuke; his height is 6 shaku, 2 bu (approximately 180.6 centimeters); he is a black male with skin like charcoal.” This substantiated Yasuke’s height and that he had black skin.
The diary includes the oldest known diagram of a game of shōgi. It is not clear, however, whether this is only a depiction of positions or Ietada was playing the game.