Nationality Under International Law


It has been shown that states are free to attribute their nationality to whomever they choose on the basis of various modes, with no, or perhaps very few, exceptions. It is an accepted general principle of law that determinations of nationality are, for the purposes of international law, within the domain reserved to each state’s municipal law, basically a reflection of state sovereignty within the system of international law and relations.

  • The general rule in relation to attribution and recognition of nationality on the international plane is found in Article 1 of the 1930 Hague Convention: It is for each State to determine under its own law who are its nationals. This law shall be recognized by other States in so far as it is consistent with international conventions, international custom, and the principles of law generally recognized with regard to nationality.

  • A related issue is when states agree among themselves to treat their own nationals as aliens, in certain circumstances, when they are dual or multiple nationals. For example, Australia entered into a Consular Treaty with Hungary that was accompanied by an Exchange of Notes according to which Hungarian-Australian dual nationals will be regarded as Australians by Hungary if they enter that country on Australian passports with visas for temporary visits, and vice-versa.

Other Considerations of Recognition of Nationality and the “Nottebohm” Case

The Nottebohm Case (Liechtenstein v Guatemala) is often cited (or confused) as dealing with issues of multiple nationality or conferment of nationality generally. This is arguably because the international Court of Justice (ICJ) applied a test of effective Nationality to the case a test which is commonly used by governments and courts in cases involving multiple nationalities.

In fact, it is uncontroverted that Mr Nottebohm was never a multiple national according to the municipal laws of the countries in question. Rather, his case involved the right of a state not to recognise another state’s attribution of nationality, and thus to exclude the second state from exercising a right of diplomatic protection.

The ICJ held that Guatemala was not obliged to recognize Nottebohm’s Liechtenstein nationality (i.e. to recognise Liechtenstein’s claim on behalf of Nottebohm), as there was no genuine or effective link between the two, other than Nottebohm’s naturalisation. It should be noted that the Court did not rule that Liechtenstein was not entitled to protect Nottebohm generally, just not vis-à-vis Guatemala.

The Court also expressly avoided comment on the validity of Nottebohm’s naturalisation under international law, Guatemala having urged it to declare the naturalisation itself invalid under general principles of law. The issue was one of specific opposability. But the case seemed to extend the principle of the genuine or effective link from the context of multiple nationalities to recognition, or opposability of nationality, generally.

But when a person is vested with only one nationality, which is attributed to him or her either jure sanguinis or jure soli, or by a valid naturalisation entailing the positive loss of the former nationality, the theory of effective nationality cannot be applied without the risk of causing confusion.


Charles G. Fenwick - Nationality may be defined as a bond which unites a person to a given State, which constitutes his membership in the particular State, which gives them a claim to the protection of that state and which subjects him to the obligations created by the laws of that State

J.G Starke - Nationality may be defined as the legal status of membership of the collectivity of individuals whose acts, decisions and policy are vouchsafed through the legal concept of the State representing those individuals.

General Bases for Non-Recognition of Nationality under International Law

Aside from the possible categories already discussed, examples include instances where the connection between the individual and the state is not deemed sufficient to warrant the state’s claim to protect an individual vis-a-vis other status. Thus:

(1) Naturalisation of nationals of other states who are unconnected to either the territory or the nationals of a State is not required to be recognized.

(2) Naturalisation of all persons of a given religious faith or political persuasion, speaking a given language, or being of a given race is not required to be recognized.

(3) Acquisition of real estate as a basis for a grant of nationality is questionable.

(4) Inhabitants of mandated and trust territories are not considered nationals of the administering State.

(5) Inhabitants of occupied territories can not be considered nationals of the occupying State.

(6) Automatic attribution of nationality upon marriage is cited by the ILC.


Once attributed, nationality has consequences on both the international and the municipal planes of law. In terms of municipal law, certain rules (rights, entitlements privileges, obligations) are applicable to nationals but not to aliens.

In the international context, Shearer lists the “international importance” of nationality as:

(1) entitlement to exercise diplomatic protection,

(2) state responsibility for nationals,

(3) duty of admission,

(4) allegiance,

(5) right to refuse extradition

(6) determination of enemy status in wartime

(7) exercise of jurisdiction.

Now let's Understand Each of them in Detail : -

1. Entitlement to exercise diplomatic protection -

  • The right involved is one of customary international law, of the state of nationality, not the individual.

  • It is unconditional and is unlimited in time, but while states may provide a right to diplomatic protection to their nationals in their municipal laws, in terms of international law its exercise is at the complete discretion of the state.

  • According to the Principle of equality, found in Article 4 of the 1930 Hague Convention on Certain Questions Relating to the Conflict of Nationality Laws, “a State may not afford diplomatic protection to one of its nationals against a State whose nationality such person also possesses”.

  • According to the principle of effective or dominant nationality (or, genuine or effective link, mentioned above), applied only vis-à-vis third states in the 1930 Hague Convention, the multiple national is to be treated as only possessing one Nationality.

2. State responsibility for nationals

  • Shearer states that “the state of which a particular person is a national may become responsible to another state if it has failed in its duty of preventing certain wrongful acts committed by this person or of punishing the person after these wrongful acts are committed”

  •  But the internationally delinquent act must be imputable to the state itself, not just to its national generally.

3. Duty of Admission

  • A state must grant its nationals entry onto its territory and allow them to reside there, and is under an obligation not to expel them

  •  This is because it is “an accepted rule of international law that states are not unless bound by treaty obligations under an obligation to grant to aliens an unconditional and unlimited right of residence, though they may not expel them arbitrarily and without just cause”. Thus a state that refuses to admit its nationals, or expels them to a state unwilling to receive them, violates a fundamental duty of positive international law in relation to territorial supremacy.

4. The Right to Refuse Extradition

  • A “state has a general right, in the absence of a specific treaty binding it to do so, to refuse to extradite its own nationals to another state requesting surrender”.

  •  Shearer notes that most relevant treaty provisions either bar such extradition absolutely provide that the states concerned “shall be under no obligation to surrender their own nationals”. He traces the origins of the practice to antiquity.

6.Determination of enemy status in wartime

  • Weis notes that nationality is sometimes used in municipal legislation as far as determining “enemy character” in wartime, but emphasises the distinction between the two notions.50 He notes that:

  • Each belligerent State is free to apply - without prejudice to existing treaty obligations its own laws for determining enemy character.... Moreover, nationals of a neutral State acquire enemy character if they have in some way, identified themselves by their conduct with the enemy, e.g., by joining his armed forces: they have become assimilated to enemy nationals. This applies even to the belligerent’s own subjects.

7. Exercise of Jurisdiction

Nationality is one or the key bases upon which states exercise jurisdiction over individuals, on a personal basis as opposed to a territorial one, jurisdiction which may be characterised as very broad. According to the protective (or security) principle of jurisdiction, “international law recognises that each state may exercise jurisdiction over crimes against its security and integrity or its vital economic interests”.


Because of the conflict of the laws of nationality of different countries, a situation often arises when a person possess nationality of more than one state. To give example of such a case is that of a woman, who after her marriage acquires the nationality of her husband and also continues to possess her original nationality. The double nationality may also be acquired by birth if parents are at the time of birth in a state whose nationality they do not possess. Consequently, treaties may provide that the person may, by their will, select their nationality.

  • The Hague conference of 1930 made an attempt to remove the difficulty arising out of double nationality in consequence of war. Article 3 to 6 of the Hague convention contain the provisions in this connection. e.g. Article 5 provides that such a person shall be treated in their state as if he has only one nationality. The third state will either recognize the nationality which is more relevant in accordance with the facts and circumstances of each individual case.

  •  Article 8 to 11 provide for the nationality of married women. In these provision, an endeavor has been made to remove the difficulties. According to the principal contained in these provisions if a woman marries, then she will automatically acquire the nationality of her husband. In the recent times the convention on nationality of married women is yet another significant attempt to remove the difficulties and problems arise out of the double nationality.


1) By Release: Some States, such as Germany., Law provides that the citizens may lose the nationality by release. In the loss of nationality by release it is necessary to submit an application for the same. If the Application is accepted, the person concerned is released from the nationality of the State concerned.

2) Deprivation: Certain States have framed some municipal laws the breach of which by its nationals results in the deprivation of their nationality. Under the American laws, service in the armed forces of a foreign State also results in deprivation of citizenship.

3) Expiration: In certain States, on account of legislation citizenship expires due to long stay abroad. A naturalist American citizen loses his nationality by having s continuance residence or three years in the territory of a foreign state of which he was formerly a national or in which the place of his birth is situated.

4)Renunciation:A person may also renounce his nationality. The need for renunciation arises when a person acquires the nationality of more than one State. In such a condition he has to make a choice as to of which country he will remain national .Finally, he has to renounce the nationality of one State. In the case of double nationality of children, the municipal laws of certain States like Great Britain give them a right on coming of age to declare whether they wish to cease to be citizens of one State. The British nationality Act of 1948 permits such a child to make a declaration of the renunciation of citizenship of the United Kingdom, but the registration of such a declaration may be withheld by the Secretary of State if made during any war