Bo Yi 伯夷 ("Uncle Yi") was a loyal subject to the last king of the Shang dynasty 商 (17th-11th cent. BCE). His personal name was Yuan 元, the courtesy name Gongxin 公信. He was the oldest son of the lord of Guzhu 孤竹 from the family Motai 墨胎.
Bo Yi was not designated to succeed his father, but his younger brother Shu Qi 叔齊 "Uncle Qi" refused to mount the throne. Both thus expressed a high degree of filial piety and are venerated by the Confucians as an example of ministers displaying righteousness and loyalty. Both left their homeland and followed the Viscount of the West (Xi Bo 西伯), the eventual King Wu 周武王 (11th cent.), founder of the Zhou dynasty 周 (11th cent.-221 BCE).
During the attack on Shang, the two brothers, as former subjects of the Shang, admonished King Wu not to destroy the kingdom of Shang, yet their pleas dit not yield success.
Disappointed about the Viscount's will to erase the Shang kingdom, they left and withdrew to the mountains near Shouyang 首陽, where they finally died of hunger because they refused to consume even the grass under the rule of the Zhou dynasty.
This story is recorded in the book Gushikao 古史考 by Qiao Zhou 譙周 from the Three Kingdoms period 三國 (220-280) that only survives in fragments. It is also to be found in fragments of the Lieshizhuan 列士傳 quoted in the collection Diaoyuji 琱玉集, and the book Jinlouzi 金樓子.
According to the geography Sanqinji 三秦記, there was a tomb of Bo Yi near Chang'an 長安 (modern Xi'an 西安, Shaanxi) of which it was said the grass growing nearby of it would prolong one's life if consumed.