Lifespan: Unknown to 11/15 of Tenshō 2 (1574)
Rank: bushō, lord of Itami Castle
Title: Governor of Yamato
Lord: Hosokawa Harumoto → Oda Nobunaga → Ashikaga Yoshiaki
Father: Itami Chikanaga
Itami Chikaoki served as a bushō during the Muromachi and Sengoku periods. He held the title of Governor of Yamato. His common names were Jirō and Sadachika. Chikaoki served as the lord of Itami Castle in Settsu Province.
The Itami clan were powerful kokujin, or provincial landowners, in Settsu and served the Hosokawa-Keichō family. In the sixth month of 1531, however, Itami Kunisuke (the lord of Itami Castle and head of the Itami clan), who had allied with Hosokawa Takakuni and Uragami Muramune, was killed during the Collapse at Daimotsu. Thereafter, the Itami clan surrendered to Hosokawa Harumoto from the branch of the Hosokawa family based in Awa Province. Meanwhile, Kunisuke’s cousin, Chikaoki, succeeded him as the lord of Itami Castle.
Service to the Miyoshi administration
In the ninth month of 1541, acting upon orders of Harumoto, Miyoshi Nagayoshi (the lord of Koshimizu Castle) launched attacks against Miyoshi Masanaga (the lord of Enami Castle), Ikeda Nobumasa (the lord of Ikeda Castle), and Shiokawa Masatoshi (based at Hitokura Castle and a member of the former faction supporting Takakuni). Chikaoki and Miyake Kunimura (the lord of Miyake Castle) appealed directly to Ashikaga Yoshiharu (the twelfth shōgun of the Muromachi bakufu) in regard to the impropriety of attacking Hitokura Castle, and, further, requested the support of Kizawa Nagamasa. Chikaoki himself led reinforcements toward Hitokura Castle, whereupon, prior to the outbreak of hostilities, the Miyoshi army led by Nagayoshi lifted its siege and, on 9/29, withdrew to Koshimizu Castle. This event is known as the Siege of Hitokura Castle. This event then led to the Battle of Taihei Temple between Miyoshi Nagayoshi and Kizawa Nagamasa ending in the death of Nagamasa.
In 1545, Chikaoki cooperated with Hosokawa Harumoto and Miyoshi Nagayoshi in battle against Hosokawa Ujitsuna (the son of Hosokawa Takakuni).
When, at the end of 1548, Nagayoshi rebelled against his lord (Harumoto), Chikaoki remained loyal to Harumoto. In the sixth month of 1549, at the Battle of Eguchi, Nagayoshi defeated Miyoshi Masanaga and then sent Harumoto fleeing in defeat and surrounded Itami Castle. Chikaoki, however, managed to defend the castle and, in the third month of 1550, through mediation by Yusa Naganori, the two sides reconciled.
In 1558, Rokkaku Yoshikata, along with Miyoshi Masakatsu (Miyoshi Masanaga’s son later known as Miyoshi Sōi) and Kōzai Motonari attempted to march upon the capital in service of Ashikaga Yoshiteru (the thirteenth shōgun of the Muromachi bakufu). Chikaoki joined Ikeda Katsumasa, Matsunaga Hisahide, and Miyoshi Nagayasu under Miyoshi Nagayoshi to oppose them.
In the fifth month of 1562, Chikaoki fought on behalf of the Miyoshi at the Battle of Kyōkō Temple between Nagayoshi and Hatakeyama Takamasa.
In 1564, after Nagayoshi died of illness, a power-struggle broke out between the Miyoshi Group of Three on one side and Matsunaga Hisahide and Miyoshi Yoshitsugu on the other side. Chikaoki sided with Hisahide and, in the fifth month of 1566, attacked Ikeda Katsumasa at his base at Ikeda Castle in Settsu. On 6/11 of the same year, Chikaoki incurred attacks by allied forces of the Miyoshi Group of Three, namely those from the Miyoshi clan based in Awa and the Sogō clan of Sanuki led by Shinohara Nagafusa who landed via the Hyōgo Inlet. After the fall on 8/17 of Tatsuyama Castle that served as Hisahide’s base in western Settsu, on 9/5, Chikaoki surrendered to the Miyoshi Group of Three. This event is known as the Battle at the Giant Buddha of Tōdai Temple.
Ashikaga Yoshiaki and three military governors of Settsu
In the ninth month of 1568, after Oda Nobunaga marched upon Kyōto to install Ashikaga Yoshiaki as the fifteenth shōgun, the Miyoshi Group of Three and Shinohara Nagafusa abandoned all of their bases in Settsu, including Akutagawayama and Koshimizu castles, and, on 10/2, retreated to Awa Province. At this time, Chikaoki and Ikeda Katsumasa surrendered to Nobunaga and received recognition of their rights to their landholdings. Thereafter, Wada Koremasa, a powerful kokujin from Ōmi and close associate of the shōgun, entered Akutagawayama Castle and the Wada, the Itami, and the Ikeda were appointed as military governors of Settsu, called the Three Military Governors of Settsu.
In the first month of 1569, the Miyoshi Group of Three crossed the Seto Inland Sea, landed in Izumi, and attacked Yoshiaki at the Honkoku Temple. Chikaoki, along with Hosokawa Fujitaka, Miyoshi Yoshitsugu, Ikeda Katsumasa, Araki Murashige and his allies from Settsu defeated the Group of Three at the Battle of Honkoku Temple.
In the sixth month of 1570, Murashige colluded with Miyoshi Nagayasu (one of the members of the Group of Three) to oust Katsumasa from Ikeda Castle. On 7/21, the Group of Three returned again, landing in Nakajima in Settsu to build Noda and Fukushima castles. Nobunaga responded by launching and expedition to Settsu and surrounding the castles. In the eighth month, Chikaoki followed orders from Yoshiaki to set-up camps in the forests of Nakashima and Tenma. Owing to a rebellion on 8/13 by the followers of the Ishiyama-Hongan Temple and the southward advance of the allied forces of the Azai and Asakura, on 8/23, the Ashikaga and Oda forces withdrew in the direction of Yamashiro. On 8/27, the forces from Awa and Sanuki led by Shinohara Nagafusa landed on the shore of Hyōgo and, at the Battle of Noda and Fukushima Castles, re-took Koshimizu Castle.
On 6/11 of Genki 2 (1571), the forces led by Nagafusa landed again in the Kinai and attacked Hatakeyama Akitaka at Takaya Castle in Kawachi. Akitaka was the brother-in-law of Nobunaga. At the end of the eighth month, Araki Murashige and Ikeda Tomomasa attacked allies of the shōgun including Chikaoki, Ibaraki Shigetomo, and Wada Koremasa, resulting in the deaths of Shigetomo and Koremasa at the Battle of Shiraikawara on 8/28. Riding the momentum of their victory over the Wada, the Ikeda forces proceeded to attack Ibaraki and Kōriyama castles, and then surrounded Takatsuki Castle defended by Wada Korenaga (Koremasa’s son). Matsunaga Hisahide and his son, Matsunaga Hisamichi, joined the Ikeda forces, setting fire to the area below the castle. Based on the report of Luís Fróis, a Portuguese missionary in Japan who had close ties to the Wada clan, on 9/9, Nobunaga dispatched Sakuma Nobumori, and, on 9/24, Yoshiaki dispatched Akechi Mitsuhide, to pursue a settlement, whereupon Murashige and the others withdrew their forces.
In 1572, following after the rebellion by Matsunaga Hisahide, Ashikaga Yoshiaki also cut ties with Nobunaga, forming a secret alliance with the Miyoshi Group of Three. Chikaoki then chose to align with Hisahide and Yoshiaki, and, in the fifth month, joined Hisahide and Miyoshi Yoshitsugu to attack Katano Castle and the territory of Hatakeyama Akitaka in Kawachi Province.
The rise of Araki Murashige and the end of the three military governors of Settsu
In the third month of 1573, Takayama Tomoteru and Takayama Ukon (father and son) were killed in Takatsuki Castle by Wada Korenaga. Moreover, in the following month, Araki Murashige at Ikeda Castle switched sides in favor of Nobunaga. Around this time, the Ikeda family included Ikeda Tomomasa of the Miyoshi faction and Ikeda Katsumasa of the faction supporting Ashikaga Yoshiaki, and it is surmised that Murashige severed ties with both factions. Prior to their killing, the Takayama (father and son) followed Murashige while elements of the former Wada and Ikeda clans were directed toward the Itami clan.
In the seventh month, Shinohara Nagafusa of Awa was murdered by Miyoshi Nagaharu during the Siege of Uezakura Castle so members of the Miyoshi faction in the Kinai could no longer receive support from Awa and Sanuki provinces. That same month, after holing-up on Makishima Castle, Ashikaga Yoshiaki surrendered at the Siege of Makishima Castle. In the eighth month, Iwanari Tomomichi (the leader of the Miyoshi Group of Three) was killed at the Second Siege of Yodoko Castle. In the eleventh month, Miyoshi Yoshitsugu took his own life at the Siege of Wakae Castle, while, in the twelfth month, Matsunaga Hisahide surrendered. On 11/15 of Tenshō 2 (1574), when Araki Murashige attacked and captured Itami Castle, Chikaoki took his own life. According to one theory, after the fall of the castle, he became a rōnin, or wandering samurai, and was later killed in action at the Battle of Sekigahara. Itami Castle was renamed Arioka Castle and became the base of Araki Murashige.