Diplomacy is an integrative art that builds intra- and inter-group relations between people of the same community and with outside communities. In pre-colonial Igbo land, it was an indigenous way of life by which children were moulded early for purposes of peaceful co-existence with all men in later life. This chapter is a review of patterns and application of diplomacy among the Igbo, and how this shaped Igbo relations within and with neighbouring communities before the advent of the Europeans. The identity theory first propounded by Henri Tajfel in 1979 was utilized to examine the reasons, means and benefits of pre-colonial Igbo diplomacy. The theory emphasizes group claims as the primary causes of conflict among individuals and groups that contend to establish their supremacy. Utilizing the inference/deductive approach, the paper argues that war, whether by an imperial power from Europe or elsewhere, is a negative approach in inter-group relations because it alters the natural order of human existence, leaving wounds that never heal, and by which memories of the war endure endlessly.