What manga do you know of, or can recommend thats based on historical events.... however loosely... maybe even traditional folklore? The two that Come to my mind are Shin Angyo Onshi (my #1 manga) which intertwines Korean historical figures and stories with magic and Vagabound which is a "fictionalized" retelling of the life of Miyamoto Mushashi, often referred to as the "Sword Saint", perhaps the most famous and successful of Japan's sword fighter.

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