Nationality is a legal relationship between an individual person and a state. Nationality affords the state jurisdiction over the person and affords the person the protection of the state. What these rights and duties are varies from state to state.
By custom and international conventions, it is the right of each state to determine who its nationals are. Such determinations are part of nationality law. In some cases, determinations of nationality are also governed by public international law—for example, by treaties on statelessness and the European Convention on Nationality.
Nationality differs technically and legally from citizenship, which is a different legal relationship between a person and a country. The noun national can include both citizens and non-citizens. The most common distinguishing feature of citizenship is that citizens have the right to participate in the political life of the state, such as by voting or standing for election. However, in most modern countries all nationals are citizens of the state, and full citizens are always nationals of the state.
In older texts, the word nationality rather than ethnicity, often used to refer to an ethnic group (a group of people who share a common ethnic identity, language, culture, descent, history, and so forth). This older meaning of nationality is not defined by political borders or passport ownership and includes nations that lack an independent state (such as the Arameans, Scots, Welsh, English, Basques, Catalans, Kurds, Kabyles, Baloch, Berbers, Bosniaks, Kashmiris,Palestinians, Sindhi, Tamils, Hmong, Inuit, Copts, Māori, Sikhs, Wakhi, Székelys, Xhosas and Zulus ).
Individuals may also be considered nationals of groups with autonomous status that have ceded some power to a larger government.
Nationality is the status that allows a nation to grant rights to the subject and to impose obligations upon the subject. In most cases, no rights or obligations are automatically attached to this status, although the status is a necessary precondition for any rights and obligations created by the state.
In European law, nationality is the status or relationship that gives a nation the right to protect a person from other nations. Diplomatic and consular protection are dependent upon this relationship between the person and the state. A person's status as being the national of a country is used to resolve the conflict of laws.
Within the broad limits imposed by few treaties and international law, states may freely define who are and are not their nationals. However, since the Nottebohm case, other states are only required to respect claim by a state to protect an alleged national if the nationality is based on a true social bond. In the case of dual nationality, states may determine the most effective nationality for a person, to determine which state's laws are most relevant. There are also limits on removing a person's status as a national. Article 15 of the Universal Declaration of Human Rights states that "Everyone has the right to a nationality," and "No one shall be arbitrarily deprived of his nationality nor denied the right to change his nationality."