The 1546 Battle of Odaihara was one of many steps taken by Takeda Shingen

Takeda Shingen

, of Kai Province, was a preeminent daimyo in feudal Japan with exceptional military prestige in the late stage of the Sengoku period.-Name:Shingen was called "Tarō" or "Katsuchiyo" during his childhood...

, one of Japan's great warlords of the Sengoku period

Sengoku period

The or Warring States period in Japanese history was a time of social upheaval, political intrigue, and nearly constant military conflict that lasted roughly from the middle of the 15th century to the beginning of the 17th century. The name "Sengoku" was adopted by Japanese historians in reference...

, in his bid to take over Shinano province

Shinano Province

or is an old province of Japan that is now present day Nagano Prefecture.Shinano bordered on Echigo, Etchū, Hida, Kai, Kōzuke, Mikawa, Mino, Musashi, Suruga, and Tōtōmi Provinces...

. He met the forces of Uesugi Norimasa

Uesugi Norimasa

was a daimyō of feudal Japan, and held the post of Kantō Kanrei, the Shogun's deputy in the Kantō. He is perhaps best known as the adoptive father of Uesugi Kenshin, one of the most famous warlords in Japanese history....

 on the plains of Odaihara, and defeated Uesugi's army while devoting a portion of his own force to the concurrent siege of nearby Shika castle

Siege of Shika

The siege of Shika castle, spanning the years 1546 to 1547, was one of many battles fought in Takeda Shingen's bid to seize control of Shinano Province. Having just defeated Uesugi Norimasa at the battle of Odaihara, Shingen made use of 300 severed heads obtained at that battle to intimidate...

. His victory at Odaihara would grant him hundreds of enemy heads to use for intimidation tactics at Shika.