This study focuses on the Origin and Development of Ethnic Militia in the Wukari Area of the present Taraba State during the period 1945-2005 using the Jukun and Tiv ethnic groups as a case study. The proliferation of ethnic oriented violence in Nigeria and in the Wukari Area in particular is a product of ethnic militia, and has become a national trend, hence constituting a threat to the survival of the state, and raises the questions of factors responsible for this development. Thus, the main objectives of the study are to analyze the major factors that encouraged the emergence of ethnic militia in the area of study. The study reveals that the evolution of ethnic militia in the study area was a by-product of colonial policies in the former Wukari Division which, among others, included direct taxation and forcible subordination of the Tiv communities in the area under the centralized pre-colonial polity of the Jukun without any regard to their peculiarities and interests. The study also reveals that the inherent contradictions in the body politics of Nigeria and Wukari area in particular in the post-colonial era characterized by winner-take-all syndrome played a vital role in the recurrent activities of ethnic militia in the study area. Thus, the continuation of this negative act among the ethnic groups in the area influenced the nature and forms of socio-political inter-course between the Jukun and the Tiv peoples in the post-colonial era. In addition, the quest for agrarian land and ownership of the Wukari Area were parts of the issues in the Jukun-Tiv conflicts perpetrated by the ethnic militia from both groups in the 1990s and 2000s. It is against this background that the study examines the evolution of these ethnic militia and the consequences of their activities in the Wukari area. In terms of methodology, the researcher collected oral data in the field through oral interviews conducted in the former Wukari Division and its environs. These oral interviews were carefully scrutinized and cross-checked with available archival materials collected from the National Archives in Kaduna, including other related secondary sources as well. The study recommends that both ethnic groups (the Jukun and the Tiv) should be encouraged to understand and respect each other‟s cultural heritage. This practice, if sincerely carried out will help in preventing those cultural shocks that served as obstacles to the co-existence of the Jukun and the Tiv in the post-colonial era.