The Zhou dynasty had been at war with the western Rong tribes since the time of Duke Xiang's grandfather Qin Zhong.
Soon after Duke Xiang ascended the throne, in 777 BC he married his younger sister Mu Ying to a Rong leader called King Feng (豐王) in an apparent attempt to make peace.
Shifu, Duke Xiang's older brother who led the defence of Quanqiu, was captured by the Rong, but was released a year later.
Marquis of Shen rebelled at the news and made an alliance with the Quanrong tribe to attack the Zhou capital Haojing, killing King You at Mount Li.
[2] To reward Duke Xiang's contribution, King Ping formally granted him a nobility rank and enfeoffed him as a feudal lord.