The main argument of this contribution is that the distinction between internal and external is at best blurred and in reality does not make much sense in the case of India’s foreign policy. It may start and end at the border and be determined by negotiations, diplomacy or brute force but there is no conclusive evidence in the literature to decide what determines what. There are important dynamics and interplays across the thin line between the domestic and international sphere especially in terms of understanding the reciprocal challenges related to how factors of culture and ethnicity relate with the legitimacy of the state. The aim of the paper serves four purposes. To unpack and give a critical overview of the debates concerned with the internal and external aspects of India’s foreign policy; situate the literature dealing more specifically with domestic issues related to culture and ethnicity and outline the main approaches involved; to give an overview of how external factors impact foreign policy conduct and relate to India’s role in defining international norms and regulations; finally the paper gives some theoretical markers, suggestions and concluding remarks.