Majority of ethnic groups in Bamenda Grasslands like the Mbum established and sustained diplomatic relations with each other since their settlement in the region based on the canon of common ancestry. Despite this, only few fondoms still maintain this doctrine as the rate of mutual connections among them diminished drastically over the past centuries due to competition for governing space and conflicts of autonomy. This study sustains the argument that marriages and royal celebrations were factors that strengthened relations among Mbum fondoms. Oral traditions and written sources were data used in carrying out this research. This study reveals that nuptial practices and royal celebrations underwent mutations without necessarily respecting the dogma of Mbum traditions. Fons gave their daughters in marriage to their counterparts to create new/strengthen relations among them. Women played significant role in conflict resolutions and the acquisition of farm/settlement land for their relatives. The introduction of Christianity and huge bride wealth hindered the fulfilment of many marriage rites in Mbum land. Marriages and royal celebrations remain vital facets of coexistence and diplomatic relations among Mbum fondoms.