The phrase "were part" can be substituted with a range of synonyms to convey the same meaning while creating variations in writing. Some possible synonyms include "were involved in," "contributed to," "played a role in," "were participants in," "were implicated in," "had a stake in," "shared in," "were engaged in," "were included in," and "were members of." These synonyms can be used in multiple contexts, such as describing group activities, business partnerships, sports teams, political movements, and social dynamics. The choice of synonym largely depends on the author's style and the tone of the text.