Lifespan: Genki 3 (1572) to 9/29 of Keichō 5 (1600)
Lord: Chōsokabe Motochika → Chōsokabe Morichika
Father: Chōsokabe Motochika
Adoptive Father: Tsuno Katsuoki
Mother: Motochika-fujin (formal wife of Motochika)
Siblings: Chōsokabe Nobuchika, Kagawa Chikakazu, Chikatada, Chōsokabe Morichika, Chōsokabe Ukon-Taifu, Chōsokabe Yasutoyo
Tsuno Chikatada served as a bushō during the Azuchi-Momoyama period. He was a retainer of the Chōsokabe clan of Tosa Province. His common name was Magojirō.
In 1572, Chikatada was born as the third son of Chōsokabe Motochika, the sengoku daimyō and twenty-first head of the Chōsokabe clan.
His father, Motochika, subdued the Tsuno, a gōzoku, or wealthy family, in Tosa. Chikatada was sent to become the adopted heir of Tsuno Katsuoki, later becoming the head of the Tsuno clan. In 1585, however, during the Conquest of Shikoku, Motochika was defeated by Toyotomi Hideyoshi whereupon Chikatada was sent to Hideyoshi as a hostage.
In 1586, following the death of Motochika’s eldest son, Chōsokabe Nobuchika, at the Battle of Hetsugigawa, Chikatada was drawn in to the succession struggle in the Chōsokabe clan. In addition to being slandered by a retainer named Hisatake Chikanao, during Chikatada’s time as a hostage, he had been on friendly terms with Tōdō Takatora, so was despised by Motochika. As a result, Motochika designated Chikatada’s younger brother, Chōsokabe Morichika, to be his successor to the family. In the third month of 1599, Chikatada was incarcerated by Motochika.
In 1600, at the Battle of Sekigahara, Morichika joined the Western Army. After the defeat, Chikatada apologized via Ii Naomasa to Tokugawa Ieyasu, and attempted to receive official recognition of the rights to his territory. Hisatake Chikanao, however, slandered him, accusing Chikatada of conspiring with Tōdō Takatora in a bid to take control of one-half of Tosa. As a result, on 9/29, Chikatada was murdered by Morichika at the Reigan Temple in the village of Iwa in the Kami District. He was twenty-nine years old. Thereafter, Morichika was scorned by Ieyasu for killing his older brother, serving as a reason for the removal of the Chōsokabe clan from their position.
The story that Morichika killed his older brother owing to Chikanao’s slander is noted in historical accounts of Tosa Province. Meanwhile, according to another account, Morichika did not heed Chikanao’s false charges, but Chikanao fabricated a story that the killing of Chikatada was ordered by Morichika to justify his murder of Chikatada. After Yamauchi Kazutoyo arrived in Tosa to replace the Chōsokabe, while touring the territory, he inquired whether there was someone who knew the details of the killing of Tsuno Chikatada. Kashiwabara Shin-no-jō, the governor of Susaki, responded that Nakahira Kiyobei was a member of the Tsuno clan so if he called upon Kiyobei, he would learn the facts, whereupon Kiyobei was called upon and informed Kazutoyo of the details regarding the demise of the Tsuno clan.