昭和刀（軍刀期）

During the Shōwa period, especially from the Second Sino-Japanese War (1937) through the end of World War II (1945), military swords (guntō) were produced in enormous quantities for Japanese military officers and NCOs. Military swords fall into three broad categories. First, industrially mass-produced blades (suranobe-tō, zōhei-tō) made from modern spring steel without traditional forging. Second, semi-traditional blades like Mantetsu-tō and Gunsui-tō. Third, legitimate Japanese swords forged from traditional tamahagane by certified smiths—Yasukuni-tōshō and jumei-tōkō—using ancient methods. Yasukuni-tōshō included Ikeda Yasumitsu, Kasama Shigetsugu, and Kajiyama Michikaze, whose works are recognized as art swords today. Among Shōwa-era masters, Gassan Sadakazu II (later Gassan Sadaichi) was designated a Living National Treasure, preserving the ayasugi-hada tradition while producing works of supreme elegance. Takahashi Sadatsugu was also designated a Living National Treasure, demonstrating outstanding skill in recreating kotō Bizen tradition. The military sword era is the most complex period in Japanese sword history, encompassing everything from industrial products to fine art. The GHQ sword confiscation destroyed many blades, though those with artistic merit were preserved. For collectors, discerning provenance and quality is crucial for this era.