The took place in 1575 near Nagashino Castle on the plain of Shitaragahara in the
Mikawa province of Japan. Forces under
Takeda Katsuyori had besieged the castle since the 17 June;
Okudaira Sadamasa, a
Tokugawa vassal, commanded the defending force. The Takeda forces attacked the
castle because it threatened Takeda's supply lines.