Yamakita Masakage

Yamakita Masakage (1529–1575) was one of the "Four Heavenly Kings of Takeda," serving both Takeda Shingen and Takeda Katsuyori, and was a fierce general who commanded an elite mounted cavalry unit clad in armor unified in red, known as the Akazonae (Red Armor Corps). Together with Baba Nobuharu, Naitō Masatoshi, and Kōsaka Masanobu, he formed the core of the Takeda military, and was particularly renowned as a genius of cavalry tactics.

Masakage originally belonged to the Takeda clan's umamawari (the commander's mounted guard unit) and accumulated military achievements by participating in numerous battles under Shingen. His horsemanship was considered unparalleled within the Takeda army, and Shingen entrusted him with command of the Akazonae cavalry. This Red Armor Corps was feared by many generals as the Takeda army's strongest shock assault unit, and under Masakage's command opened decisive breakthroughs in countless battles.

After Shingen's death, Masakage continued to serve Takeda Katsuyori. In the Battle of Nagashino in 1575, he faced direct confrontation with the rifle units of the Oda-Tokugawa allied forces. It is said that Masakage was aware that tactically, cavalry charges were disadvantageous against massed rifle fire, but he carried out the charge in obedience to his lord Katsuyori's orders. In this battle, Masakage fell in combat at the age of 47.

Regarding swords, Masakage was known among Takeda military leaders as one who particularly valued practical combat blades. Swords forged by swordsmiths of Kai (Yamanashi) were highly regarded as durable combat blades, and the Akazonae cavalry commanded by Masakage boasted the highest standard in their equipment. Masakage's wearing sword is passed down as "Yamakita's Single Blade" and has become a symbolic presence in the sword culture of mounted warriors.

After Masakage's death, the tradition of the Red Armor Corps was inherited by Ii Naomasa (who employed former Takeda retainers and formed the Ii Akazonae), and continued to be transmitted in later eras as a proud military uniform of warlords. Yamakita Masakage, who commanded the Takeda army's strongest shock assault unit, is highly regarded even today as a warlord who embodied the pinnacle of cavalry tactics in the Sengoku Period.