This bachelor's thesis offers a way to contextualize the contributions of the British colonial legacies towards ethnic cleavages and political instability in post-colonial Burma in order to investigate the context of issue concerning the marginalization of Rohingya ethnic minority group in Arakan State of Western Burma. It will be examined through the historical research method that will be employed as a tool to conduct the analysis and synthesis of the similarities patterns in the case of post-colonial Africa that share a common focus and goal in a way that produces knowledge. The investigated questions are as followed: (i) In what way have British colonial legacies contributed to ethnic cleavages and political instability in postcolonial Burma, (ii) How can it explain the context of issue concerning the marginalization of Rohingya ethnic minority group in Arakan State of Western Burma, and (iii) Are there similarities or differences between the colonial legacies contributions to ethnic cleavages and political instability in post-colonial Burma and Africa? In order to conduct a comprehensive analysis, this thesis employs the theory of post-colonial by using the concepts such as colonial style, direct and indirect rule, divide and rule, politicized ethnicity as well as cycles of disproportionate ethnic rule. This thesis argues that the British colonial contributions towards ethnic cleavages and political instability in post-colonial Burma are important to investigate in order to generate understanding of the complex situation of the marginalization of the Rohingya ethnic minority in Arakan State of Western Burma.