This study look at the linkage between opposition politics, identity political mobilization, and insecurity in Southern Taraba State, Nigeria, from 1999 to 2023. Since the dawn of the Fourth Republic, political rivalry in the state and by extension the region has increasingly been determined by ethnic, religious, and communal identities, which political actors have employed to mobilize support, secure electoral gain, and challenge contending groups. The study investigates how opposition politics contributed to the politicization of identity and how such mobilization influenced the nature and persistence of insecurity in Southern Taraba. The study is anchored on social identity theory as its analytical framework. The methodology adopted in this study is the qualitative historical methodology, relying on both primary and secondary sources, including oral interviews, government reports, newspapers, books, and scholarly publications. The study reveal that opposition political activities by the actors in the area often create ethnic and religious divisions, heightened perceptions of exclusion and ostracism, and thus contributed to election violence, ethnic skirmishes, population displacement, and loss of lives and property. The study further demonstrates that the manipulation of identity for political purposes weakened social cohesion and undermined peace-building efforts in the region. The study averred that the linkage between opposition politics and identity politics constituted a principal influence in the reappearance of insecurity in Southern Taraba between 1999 and 2023. The study recommends the push for inclusive governance, agenda-based governance, inter-group negotiation, and institutional reforms aimed at reducing identity manipulation and fostering sustainable peace and democratic stability in the area.