User blog comment:JoAlter/Nagao Kagetora/@comment-32751919-20190313235236/@comment-25848535-20190314005017

Ahh.... just looked up again... indeed you're right!

Theory
Uesugi Kenshin was also, according to a contemporary Japanese historian Tomeo Yagiri, a woman. As a possible rationale for a female Kenshin living as a man: because the leader of the clan had to be a man, or the shogun could divide up their lands and give them away. Evidence from this theory is that Kenshin had severe stomach cramps on a monthly basis around the 10th of the month. He actually programmed his military campaigns around that. The cause of Kenshin's death is recorded as a form of uterine cancer. Kenshin had a feminine appearance, had no children, and did not own a harem.

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