In which Part of the Constitution, details of citizenship are mentioned ?

The details of citizenship in the Indian Constitution are contained in Part II, which encompasses Articles 5 to 11 [1][t1]. These provisions primarily identify the categories of persons who became citizens of India at the time of the Constitution's commencement on January 26, 1950 [c1][t5]. Specifically, Article 5 deals with citizenship by domicile, while Articles 6 and 7 address the rights of persons who migrated from or to Pakistan [t1][t3]. Article 9 clarifies that individuals voluntarily acquiring foreign citizenship lose their Indian status [t2][t10]. Because the Constitution does not provide permanent or elaborate laws for the acquisition or loss of citizenship post-1950, Article 11 empowers the Parliament to enact legislation for such matters, leading to the Citizenship Act of 1955 [c1][t1][t9]. In contrast, Part I deals with the Union and its territory, Part III with Fundamental Rights, and Part IV with Directive Principles of State Policy [t6].

Sources

1. [1] Indian Polity, M. Laxmikanth(7th ed.) > Chapter 7: Citizenship > CONSTITUTIONAL PROVISIONS > p. 63