Lifespan: Unknown to 8/14 of Eiroku 11 (1568)
Other Names: Akitoshi, Yoshikoto; [Childhood] Senkamemaru, Shinjūrō; [Common] Yamashiro-no-kami, Sakon-shōkan, Tajima-no-kami
Title: Governor of Yamashiro, Governor of Tajima, General of the Left Division
Clan: Hita → Tachibana
Lord: Ōtomo Yoshiaki → Ōtomo Yoshishige
Father: Hita Chikakata
Adoptive Father: Tachibana Akimitsu
Wife: Daughter of Yasutake Akinori
Children: Chikayoshi (according to one theory, he is the same individual as Bekki Chikakata)
Tachibana Akikoto served as a bushō during the Sengoku period. He was a retainer of the Ōtomo clan. Akikoto served as the seventh head of the Tachibana clan and as the lord of Tachibanayama Castle in Chikuzen Province.
The Tachibana were and illegitimate branch of the Ōtomo clan descended from Ōtomo Sadatoshi.
Akikoto is deemed to have been the natural, second son of Hita Chikakata. Later, he was adopted by Tachibana Akimitsu, the head of the main branch of the Tachibana. He was a grandson of Ōtomo Chikatomo.
Akimitsu and Akikoto each received one of the characters in their names from Ōtomo Yoshiaki and the Tachibana served as retainers of the Ōtomo from this era.
In 1550, after an attack by retainers against Yoshiaki and his family known as the Collapse on the Second Floor, Yoshiaki was succeeded by his son, Ōtomo Yoshishige (Sōrin). During the period from 1558 to 1570, Akimitsu was murdered. As a result, Akikoto inherited the headship of the clan and occupied Tachibanayama Castle.
Perhaps owing to his resentment over the loss of his father, in 1564, Akikoto joined a revolt against Sōrin, killing Netabi Naotomo, a yoriki, or security officer. From 4/27 to the fifth month of Eiroku 8 (1565), Akikoto was attacked by Yoshihiro Akimasa and Bekki Akitsura. After a retainer named Yasu Zusho-no-suke was killed by Yufu Korenobu (under the command of Akitsura), Akikoto fled. Later, he was pardoned by Sōrin and granted castles to the east and west of Mount Tachibana to divide with the Nuruyu clan. The reasons for the pardon are uncertain. According to one account of clans in Kyūshū, there is a different story that he took his life at this time.
In 1568, Akikoto was lured away by Mōri Motonari and, together with Takahashi Akitane, acted in concert with an attack by the Mōri forces by launching another revolt. At this time, he killed another security officer named Komono Muneshige and attacked Nuruyu Yūsen at Shiratake to the west of Tachibanayama Castle but failed to capture him. After receiving a report from Yūsen, Sōrin became upset and directed Bekki Akitsura, Yoshihiro Shigenobu, and Usuki Akisumi to surround the castle. From the fourth to seventh months, Akikoto, together with Yasutake Minbu, Shimizu Munetomo (from the Mōri army), Harada Chikatane (a kokujin from Chikuzen), and Etō Owari-no-kami mounted a defense but were betrayed by a retainer named Noda Uemon-no-taifu who was lured away by Bekki Akitsura and, on 7/4, the castle fell. On 7/23, Akikoto took his own life. After the Ōtomo army was informed of the betrayal by Uemon-no-taifu, he was beheaded by Kamado Kageyu-no-jō 鎮意 and only his head was sent to Bungo. Under another theory, he surrendered but was not not forgiven for joining another rebellion and executed.
Akikoto’s heir, Tachibana Chikayoshi, survived but owing to the circumstances Sōrin was not supportive of reviving the Tachibana family. In 1571, Sōrin decided to have Akitsura inherit the vestiges of the Tachibana family but was not formally permitted to adopt the Tachibana family name so Akitsura did not do so at this time. Chikayoshi was either the natural son of Akikoto or adopted from the Bekki clan. In the latter case, Yamashiro-no-kami Chikayoshi was the son of Bekki Chikahisa of the Katagase-Bekki clan appears to be the same individual but this cannot be confirmed from genealogical records.