Siege of Kojinyama
1544 CE.
Shown on the map at 35.965°, 137.992°.
In the 1544 siege of Kojinyama, Takeda Shingen continued his invasion of Shinano Province's Ima Valley, seizing Kojinyama fortress from the Tozawa family.
Text from the Wikipedia article Siege of Kojinyama, licensed CC BY-SA 4.0.