Islam has a long-standing and standard tradition of maintaining peace, which emphasises prevention through moral course and countering through legal responses. The Northeast Nigeria is known for its tranquillity over many centuries, which is attributed to the role that Ulama play in peacebuilding. Unfortunately, the seemingly lasting peace was disrupted vehemently by the phenomenon of insurgency, which has harboured both domestic and international conglomerates of criminal activities for nearly two decades now. One institution that is instrumental and influential in preventing violence and countering it is the Ulama. Using in-depth face-to-face interviews, this study examines how Ulama strove hard in preventing Boko Haram from exploding into violence by engaging the extremists in dialogue in its inception, debates and public lectures and alerting the public and policymakers on the dangers of the ideology harboured by the then movement. The data comes from interviews conducted with a special category of Ulama who are active in preventing and confronting extremists in order to combat radicalisation. The content analysis method was used for the analysis. The study shows that the Ulama have made efforts to apply the Islamic peacebuilding strategies that prevented violence in the early days of Boko Haram’s activities, and that they are still using tactics of the Islamic process of deradicalisation in the Northeast. It is suggested, among other things, that these Ulama should be fully supported and funded to develop a model that successfully curbs the current violence while preventing such occurrences in the future.