He was the second son of Xiao'ao, and brother of the previous ruler, Fenmao, whom he is rumored to have murdered in 740 BC in order to usurp the throne.

With the power of Chu growing by the day, King Wu became dissatisfied with the title of Master (子) and sought to better himself.

In the summer of the thirty-seventh year of his reign, 704 BCE, at the time of King Huan of Zhou, he invited the leaders of the other vassal states to a meeting at Shenlu (沈鹿)[D].

Qu Xiao underestimated the enemy and became trapped between Lu Nomads (卢戎) and the Luo army on the borders of the state.

King Wu took responsibility for the defeat and pardoned all remaining soldiers who had taken part in the battle, although he already ordered the amputation of their right feet.