The chronology of his reign is disputed but is generally thought to have begun around 1046 BCE and ended with his death three years later.

In most accounts, his older brother Bo Yikao was said to have predeceased his father, typically at the hands of King Zhou of Shang, the last king of the Shang dynasty; in the Book of Rites, however, it is assumed that his inheritance represented an older tradition among the Zhou of passing over the eldest son.

Upon his succession, Fa worked with his father-in-law Jiang Ziya to accomplish an unfinished task: overthrowing the Shang dynasty.

During the ninth year of his reign, Fa marched down the Yellow River to the Mengjin ford and met with more than 800 dukes.

[3] He constructed an ancestral tablet with his father's posthumous name as King Wen and placed it on a chariot in the middle of the host; considering the timing unpropitious, though, he did not yet attack Shang.