Nationality is a legal bond linking an individual to a particular state, establishing a reciprocal relationship of allegiance and protection. It signifies membership in a nation-state under international law and carries both rights and duties. Rights include diplomatic protection abroad, the right to enter and reside in the state, and access to consular assistance, while duties encompass obedience to laws, taxation, and, in some states, compulsory service. The International Court of Justice, in the Nottebohm case, emphasized that nationality must reflect a “genuine link” between the individual and the state to ensure legal recognition internationally.

Modes of Acquisition of Nationality:

• Jus Sanguinis (Law of Blood): Nationality by descent from a parent who is a national, regardless of place of birth; common in Europe and Asia.
• Jus Soli (Law of Soil): Nationality by birth within a state’s territory, irrespective of parental nationality; prevalent in common law countries like the USA and Canada.
• Naturalization: Voluntary acquisition after meeting conditions such as residence, language proficiency, and good character.
• Marriage: Acquisition through a spouse’s nationality, sometimes requiring additional legal processes.
• Option: Individuals may choose nationality during state succession.
• Resumption: Reacquiring nationality previously lost.
• Adoption: Children may acquire the nationality of adoptive parents.

Nationality vs. Citizenship:
Nationality is primarily an international law concept, indicating state membership and granting rights like diplomatic protection. Citizenship is a domestic law concept, conferring political and civil rights, such as voting, holding office, and full participation in public life. All citizens are nationals, but not all nationals are citizens. In India, Articles 5–11 govern citizenship, and nationals enjoy full political rights, making the terms largely synonymous domestically. Nevertheless, the conceptual distinction remains important in international legal contexts for determining state responsibilities and individual protections.