Yoshihime

Yoshihime (Tenbun 17 (1548) – Genna 9 (1623)) was born at Yamagata Castle as the daughter of Mogami Yoshimori, a Sengoku-era daimyo of Dewa Province. She was the younger sister of Mogami Yoshiaki, two years his junior. In Eiroku 7 (1564), she married Date Terumune, lord of Yonezawa Castle, and in Eiroku 10 (1567) she gave birth to her eldest son, Bontenmaru (later Date Masamune). The following year she bore a second son, Kojirō.

Whenever military tensions arose between the Date and Mogami families, Yoshihime is said to have gone herself to the field camp and acted as a go-between for the two sides. She is reported to have stepped in during confrontations between the two families, including in Tenshō 6 (1578) and during the Ōsaki War of Tenshō 16 (1588). Caught between her natal family and her husband's family, she nonetheless played an important role as a political mediator.

Yoshihime's name is most widely known through the alleged attempt to poison Masamune in the 4th month of Tenshō 18 (1590). According to traditions such as the Teizankō Jike Kiroku, Yoshihime tried to place her second son, Kojirō, at the head of the Date family and put poison in Masamune's meal. Masamune escaped harm, however, and instead had Kojirō cut down, and Yoshihime is said to have fled to her natal Mogami family.

Recent research, however, has raised strong doubts about the historicity of this incident. Letters including those of the Zen master Kosai Sōitsu suggest that Yoshihime actually left for Yamagata around Bunroku 3 (1594), four years after the year in which the incident is said to have occurred, so the chronology does not match the tradition. Moreover, even in the period said to follow the incident, affectionate letters continued to be exchanged between Masamune and Yoshihime. In Bunroku 2 (1593), Yoshihime sent money and a waka poem to Masamune while he was stationed in Korea, and a reply from Masamune survives in which he wrote, "I long to see you just once more." Because of these contradictions, it has recently been suggested that the poisoning attempt was a staged event meant to unite the divided Date retainers, or an excuse to explain to Toyotomi Hideyoshi the delay in joining the Siege of Odawara. Whether it actually happened remains undetermined to this day.

After the Mogami clan had its domains confiscated in Genna 8 (1622), Yoshihime relied on Masamune and moved to Sendai. She died on the 16th day of the 7th month of Genna 9 (1623), at the age of 76. Her Buddhist cloister name (ingō) was Hōshun'in. As a woman of a Sengoku daimyo house who quietly supported her son Masamune's establishment of power, her reputation remains a subject of debate to this day, together with the question of whether the poisoning tradition is true.