三方原之戰
In early 1573, Shingen decided to make a drive for Kyoto at the urgings of the shōgun Ashikaga Yoshiaki, while seeking a route from Kōfu to Kyoto, Shingen moved to challenge the Oda–Tokugawa alliance in the Battle of Mikatagahara, this battle was one of the most famous battles of Takeda Shingen's campaigns, and one of the best demonstrations of his cavalry-based tactics. It was also one of Tokugawa Ieyasu's worst defeats, and complete disaster was only narrowly averted. After his victory, Shingen led a formidable force of over 30,000 into Tokugawa territories in Tōtōmi, Mikawa, and Mino.