The Masamune is named after Masamune Okazaki, a legendary Japanese blacksmith of the Kamakura Era employed under the Kamakura Shogunate. He was famous for his forging process of soshu kitae and nijuba, the strongest method for the body of katana, layering different consistencies of carbon steel for tensile composition and in such a way they were forged twice, and cultivating the aesthetics of katana through having refined and merged traits of quality with those of beauty.
His works were often compared to those of Muramasa, and sometimes mistaken for the other in fiction or fantasy novels, though always the better of the two. According to legend, the two swordsmiths set a sword of their making into a nearby stream as contest to see who made the better sword, with Masamune's blade said to have ignored all things that came near it. Though Muramasa belittled Masamune, a monk came to be the final judge and praised Masamune's swords for having benevolence, cutting only what it was meant to cut while Muramasa's cared little for what it cut. From this tale, Masamunes are said to be the marks of an internal peaceful and calm warrior, the opposite of Muramasas who were deemed bloodthirsty and cursed blades.
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