Narrow Road To The Deep North 11

Taira no Atsumori was a 15 year-old samurai, famous for his early death in single combat at the Battle of Ichi-no-Tani, in 1184. Atsumori engaged Kumagai Naozane, a Minamoto ally, and was killed. Kumagai had a son the same age as Atsumori, and his great remorse, coupled with his consequent taking of priestly vows, caused this otherwise unremarkable event to become renowned for its tragedy. The legend of Atsumori's death was poignantly profiled in Tale of the Heike. The Taira had been scattered by Yoshitsune's attack from the Ichi-no-Tani cliff. Kumagai no Jirō Naozane, scanning the beach for fleeing soldiers, spotted the young Atsumori swimming toward the fleeing vessels. Kumagai taunted him with his fan.

“I see that you are a Commander-in-Chief. He said. “It is dishonorable to show your back to an enemy. Return!” 
The two grappled on the beach, but Kumagai was too powerful. He knocked off Atsumori's helmet to deliver the finishing blow, only to be struck by the beauty of the young noble. Atsumori was ‘sixteen or seventeen years old, with a lightly powdered face and blackened teeth- a boy just the age of Naozane's own son...’ Kumagai, wishing to spare him, asked for his name, but Atsumori refused, indicating that he was famous enough that Kumagai's superiors would recognize his head when it was time to assign rewards. At that moment, other Minamoto warriors arrived at the scene, and Kumagai knew that if he didn't kill Atsumori, they surely would. Kumagai reasoned that it was better if he killed Atsumori, because he could offer prayers on his behalf for the afterlife. Crying, Kumagai beheaded the boy. Searching the body for something to wrap the head in, he came across a bag containing a flute. He realized that Atsumori must have been one of the soldiers playing music before the battle and thought, ‘There are tens of thousands of riders in our eastern armies, but I am sure none of them has brought a flute to the battlefield. Those court nobles are refined men!’ The beheading of was what led Kumagai to become a Buddhist monk.
This was classical Japanese tragedy. Atsumori was a courtier and poet, and not prepared for battle. He carried a flute, evidence of his peaceful courtly nature, and his youth and naïveté. Kumagai, the older seasoned warrior, noted that none of his fellow Genji Minamoto warriors were cultivated to the point where they would ride into battle with a flute.

The Noh play by Zeami Motokiyo, came later with the ghost song that Nobanuga would adopt as his theme. Identified as his since 1549, it would summarize his life.