was a samurai retainer to the Takeda clan during Japan's 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...

. Fighting for the Takeda at the battle of Nagashino

Battle of Nagashino

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 17th of June; Okudaira Sadamasa , a Tokugawa vassal, commanded the defending force...

, he was moved by the bravery of Torii Suneemon, an opposing samurai who risked his life, escaping from the besieged castle to seek reinforcements from Tokugawa Ieyasu

Tokugawa Ieyasu

 was the founder and first shogun of the Tokugawa shogunate of Japan , which ruled from the Battle of Sekigahara  in 1600 until the Meiji Restoration in 1868. Ieyasu seized power in 1600, received appointment as shogun in 1603, abdicated from office in 1605, but...

, only to be captured and crucified by the Takeda; from then on, Ochiai used an image of Torii Suneemon on the cross as his standard.