Within the 21st century, Cameroon has faced acute humanitarian crises, in the East, Far North, North and South West Regions of Cameroon. With the case of the East Region of Cameroon, there has been annual yearly influx of over 129.293 refugees from Central African Republic since 2009, indexed by UNHCR Data Base, giving an annual percentage of 55%. Cameroon faced with acute humanitarian challenges most especially in the East Region of Cameroon; the UNHCR came into play to grant relief to the vulnerable refugees. This Historical chronicle handles measures taken by the UN-refugees organ in humanitarian assistance to the refugees from Central African Republic within the East Region of Cameroon. The first part, takes a look at background of the study and the civil unrest in Central African Republic which resulted to massive influx of refugees into the East Region of Cameroon. The second looks at the establishment of UNHCR and the concept of humanitarian diplomacy within the humanitarian system. The third looks at the legal normative international legal instruments relating to status and protection of refugees.