In the autumn of the same year, he swore a covenant with Song at Su (宿), which, according to the Zuo Zhuan, was Lu's first diplomatic contact with that state.
However, Duke Yin eventually agreed to a covenant in the autumn of the same year, conducting the ceremonies at Tang (唐).
Soon after, in order to establish legitimacy, he forged an alliance with nearby powers Song, Chen, and Cai to attack Zheng, which had been on unfriendly terms with Wey for generations.
After multiple expeditions in a year, in autumn, Duke Shang of Song [zh] sent an envoy to Lu to seek support.
In spring 718 BC, Duke Yin planned to visit the fisheries at Tang (唐), a place near the Lu border.
This attracted expostulation from an official named Zang Xibo [zh], who remonstrated that "a ruler is the one who guides the people into the right paths and the proper usage of objects" and that the procurement of ordinary articles was "the affairs of menial laborers, and the duties of petty officers.
Duke Yin showed contrition after Zang Xibo's death in the winter of the same year, saying, "My uncle[b] was resentful of me, the unworthy one.
In spring 713 BC, Duke Yin made an alliance with Qi and Zheng to attack Song at Zhongqiu (中丘).