Lifespan: Tenbun 5 (1536) to 4/9 of Tenshō 12 (1584)
Rank: bushō, daimyō
Lord: Oda Nobuhide → Oda Nobunaga → Oda Nobutada → Oda Hidenobu → Hashiba Hideyoshi
Father: Ikeda Tsunetoshi
Children: Motosuke, Sen, Terumasa, Nagayoshi, Nagamasa, Wakamandokoro, Tenkyūin, daughter (formal wife of Asano Yukinaga), daughter (formal wife of Oda Katsunaga), Nanjō
Ikeda Tsuneoki served as a bushō and daimyō during the Sengoku and Azuchi-Momoyama periods. He was one of four senior retainers of Oda Nobunaga who participated in the Kiyosu Conference to decide upon Nobunaga’s successor. His sons included Ikeda Motosuke and Ikeda Terumasa.
Tsuneoki was the lord Inuyama Castle in Owari Province, Hyōgo Castle in Settsu Province, and Ōgaki Castle in Mino Province. His common name was Katsusaburō. He also used the self-proclaimed title of Kii-no-kami. In later years, after entering the priesthood, he adopted the name of Shōnyū. In certain military chronicles, his real name is referred to as Nobuteru, but this cannot be authenticated from older sources written during this period.
In 1536, Tsuneoki was born as the son of Ikeda Tsunetoshi, a retainer of the Oda clan of Owari Province. His mother was Yōtokuin. There are assorted theories as to whether he was from Owari, Mino, Settsu, or Ōmi province. According to the Shinchō kōki, an authenticated biography of Oda Nobunaga, an individual from the village of Isshiki in the Kaitō District of Owari served as a yoriki, or security officer, of Tsuneoki, and there is a basis that he is from this area. His father, Tsunetoshi, died early. His mother, Yōtokuin, served as the nursemaid for Oda Nobunaga and later became a consort of Nobunaga’s father, Oda Nobuhide.
During his childhood, Tsuneoki worked as a servant of the Oda clan. In 1560, he participated in the Battle of Okehazama; in 1565, the invasion of Mino Province; and, in 1570, the Battle of Anegawa. He became the lord of Inuyama Castle on the border of Owari and Mino provinces and was awarded 10,000 kan. Thereafter, Tsuneoki joined, in 1571, the Burning of Mount Hiei to subdue the followers of the Ishiyama-Hongan Temple; attacks against the Nagashima Ikkō-ikki, and, in 1573, the Siege of Makishima Castle. In 1574, he entered the mountain fortress of Ori Castle in eastern Mino to pin-down Akechi Castle after it was taken by Takeda Katsuyori. Tsuneoki was associated with Oda Nobutada, but, in 1580, after defeating Araki Murashige (who resisted Nobunaga in the Siege of Hanakuma Castle) Tsuneoki occupied his former territory.
In the third month of 1582, at the Conquest of Kōshū by the allied armies of the Oda and Tokugawa, Tsuenoki deployed his two sons, while Nobunaga ordered Tsuneoki himself to stay behind to defend Settsu Province. On 6/2 of Tenshō 10 (1582), Nobunaga died in a coup d’état by one of his senior retainers, Akechi Mitsuhide, in an event known as the Honnō Temple Incident. Tsuneoki converged with Hashiba Hideyoshi who rushed back to the capital with his army from an invasion of the western provinces. At the Battle of Yamazaki, Tsuneoki led a vanguard division of 5,000 soldiers in the right wing of the formation, defeating Mitsuhide, serving as a veteran of the Oda family.
At the Kiyosu Conference to determine the successor to the Oda family, Tsuneoki joined Hideyoshi and Niwa Nagahide by backing Nobunaga’s lineal grandson, Sanpōshi (Oda Hidenobu), who was an infant at the time, in opposition to Shibata Katsuie. With respect to the re-allocation of territory, Tsuneoki received a fief of 120,000 koku in Settsu comprised of Ōsaka, Amagasaki, and Hyōgo. In 1583, Tsuneoki did not participate in the Battle of Shizugatake, but received 130,000 koku in Mino Province and entered Ōgaki Castle while his son, Ikeda Motosuke, entered Gifu Castle.
In 1584, at the Battle of Komaki-Nagakute against the allied forces of Tokugawa Ieyasu and Oda Nobukatsu, attention was given to his course of action, but, in the end, he joined on the side of Hideyoshi. In the event of victory, he was promised to receive Owari Province. At the outset of fighting, he attacked Inuyama Castle, then stopped at Jōjō Castle, and, together with Miyoshi Nobuyoshi (later known as Toyotomi Hidetsugu), Mori Nagayoshi (Tsuneoki-s son-in-law), and Hori Hidemasa, attempted to attack Ieyasu’s main base in Mikawa Province. In the first half of the battle, a bullet struck his saddle, causing him to fall from his horse and, along with Nagayoshi, died in battle at Nagakute after being stabbed by a spear wielded by Nagai Naokatsu. Tsuneoki was forty-nine years old. His eldest son, Motosuke, was also killed in action so his second son, Terumasa, succeeded him as the next head of the clan.
His remains were taken by Tokugawa forces initially to be buried in Shinkyo in Tōtōmi Province. Later, he was re-interred at the Jiun sub-temple on the grounds of the Myōshin Temple in Kyōto.