This dissertation examines the reciprocal relationship between ethnic nationalism and political development in Pakistan. The nineteenth century was marked by the rise of the concept of nationalism and as a result many new states emerged on the World map by the end of the Second World War The end of the twentieth century witnessed the resurgence of ethnicity in the world. Ethnicity is a phenomenon and when it provides bases for nationalism, it is called ethnic nationalism. The origin of ethnicity is primordial but its political manifestation is constructed. Ethnic nationalism is commonly associated with political development. Though there are many aspects of political development but from 1970s onward, democracy has taken a front seat and countries are being studied and analyzed in terms of democratic development. The last decade of twentieth century established the supremacy of democracy and fall of communist empire proved that democracy is the most desirable form of government in the world. But many countries particularly developing states are suffering from the dilemma of political and democratic instability and many scholars are of the view that ethnic conflict is a major cause of this democratic crisis. But this fact can not be ignored that relationship between ethnic nationalism and political development is reciprocal and ethnicity can not be viewed as a negatively. No country in the World can claim to be homogeneous but despite of that, many developed countries are successfully able to sustain a democratic system. So it becomes pertinent to analyze the issue of political under development in ethnically diverse countries. Pakistan is a country plural in character. Even before partition, the Muslim majority areas of Sub-Continent were not ethnically homogenous and there were ethnic loyalties triggering ethnic based movements in those areas during the independence struggle. The decentralized future frame work presented by Muslim League was more appealing to these provinces and regions as compare to All India National Congress and finally Pakistan came in to existence. Even after partition, the dilemma of ethnic conflict could not be resolved. Pakistan experienced different constitutions and many times its political process had been derailed. After losing its eastern part, the country is still confronting with the issue of identity crisis. Democracy could not establish its roots and Pakistan stands at the crossroad in search of a stable state. Centralized politics is making the issue more problematic. Provincial concerns are intensifying and complex relationship of democracy and ethnic nationalism remains unresolved. This is an attempt to find out the root cause of the problem in search of real democratic political system.