In the spring of 656 BC, Duke Xi invaded Cai along with the states of Qi, Song, Chen, Wey, Zheng, Xu, and Cao.
In the winter of the same year, a Lu army led by Prince Zi (茲) attacked Chen together with forces from Qi, Song, Wey, Zheng, Xu, and Cao.
In 655 BC, Duke Xi met with the rulers of Song, Chen, Wey, Xu, and Cao as well as the Crown Prince Zheng of Zhou at Shouzhi (首止) in an effort to support him over Prince Dai (帶), who their father, King Hui of Zhou, preferred as heir.
In 643 BC, Duke Huan of Qi, one of the Five Hegemons, died, triggering a war of succession among six of his sons.
In 639 BC, the state of Zhu conquered Xuqu [zh], the ruler of which sought refuge in Lu.
Cheng Feng, Duke Xi's mother, convinced him to restore the state of Xuqu, her origin.
The next spring, Duke Xi personally lead an army and attacked Zhu, restoring Xuqu.
Zang Wenzhong (臧文仲), one of his officials, warned: Even for the former kings, with their bright virtue, there was nothing they did not consider difficult, nothing they did not fear.
[3]The Duke did not heed his advice, and was defeated by the Zhu army at Shengxing (升陘) on 20 July 638 BC.
When asked by Duke Xiao whether the people of Lu were afraid of him, Zhan Xi answered to the contrary.
In spring 633 BC, the Duke of Qǐ (杞, not to be confused with the previously-mentioned 齊) visited the Lu court.
Zhu was taken off guard, allowing Duke Xi to take a city named Zilou (訾婁) and avenge the defeat at Shengxing twelve years prior.