Citizenship Loss and Deprivation in the European Union (27 + 1) law of perpetual allegiance applied more particularly to natural-born subjects, i.e., nationals by origin, considered as perpetual members of the people by the sole virtue of their birth within the territory of the Monarch. Perpetual allegiance was profoundly challenged in the late 18th and 19th century. The conflict between England and the United States created an opportunity for the American common law system to break with the doctrine of perpetual allegiance. On the ground of perpetual allegiance due to the Monarch, English military authorities forced American citizens born English to join the royal navy, which was one of the factors that triggered the 1812 Anglo-American War. The contractual vision of American citizenship eventually led to the adoption of the 1868 Expatriation Act – which states that “the right of expatriation is a natural and inherent right of all people” – and the adoption of the ‘Bancroft treaties’ between the United States and dozens of countries, which provided for the loss of citizenship of naturalised American citizens relocated to their country of origin. The American common law system thus abandoned the principle of perpetual allegiance and was soon followed by the United Kingdom. The Naturalisation Act passed in 1870 provided, for the first time in British history, the possibility to renounce British nationality in certain circumstances through a “declaration of alienage,” or automatically in case of foreign naturalisation. The principle of perpetual allegiance died in the 19 th century, with the increase of mobility and the liberal recognition of the individual right of expatriation. By contrast, continental law had never adopted the principle of perpetual allegiance (see infra, 3.1.1), and thus allowed individuals to renounce their nationality. In France, for instance, it was possible for individuals, at least since the 19th century, to ask for a release of allegiance, pronounced by the government on a discretionary basis.10 2.1.2. International and European Legal Framework The right to change one’s nationality was then enshrined in the 1948 Universal Declaration of Human Rights, providing at article 15(2) that “No one shall be arbitrarily deprived of his nationality nor denied the right to change his nationality.” (emphasis added) This fundamental right to change one’s nationality is nevertheless not an absolute one. States are still justified in limiting the loss of nationality of their citizens in two special circumstances. The first one is linked to the general prohibition of statelessness. An individual cannot renounce his or her nationality if he or she becomes stateless. The 1961 Convention on the Reduction of Statelessness clearly stated in article 7(1)(a) that “If the law of a Contracting State permits renunciation of nationality, such renunciation shall not result in loss of nationality unless the person concerned possesses or acquires another nationality.”11 The second circumstance in which a State can legally refuse the renunciation is when the individual does not reside abroad. Two main reasons support this rule: [1] to avoid individual manipulation of a citizen trying to escape national duties (such as military service) by using a foreign nationality while still residing in the country whose nationality he or she wants to relinquish; [2] to maintain the genuine link principle which links nationality to habitual residence. Article 6 of the 1930 Convention on Certain Questions Relating to the Conflict of Nationality Laws was the first international treaty to formulate in general terms the rule according to which one of two involuntarily acquired nationalities can be renounced with the authorisation of the State, and that “[t]his authorisation may not be refused in the case of a person who has his habitual and principal residence abroad […].” The 1963 European Convention on the Reduction of Cases of Multiple Nationality generalised this rule stating in article 2 that “(1) A person who possesses the nationality of two or more Contracting Parties may renounce one or more of these nationalities, with the consent of the Contracting Party whose nationality he desires to 10 Lepoutre, J. (2020). Nationalité et Souveraineté. Paris: Dalloz, 279. 11 The 1961 Convention provides for an exception when articles 13 and 14 of the 1948 UDHR are at stake, i.e., freedom of movement (especially the right to leave one’s own country) and the right to seek and to enjoy asylum from persecution in other countries. In other words, states shall not use statelessness prohibition as a way to jeopardise the freedom of movement and the right to seek asylum. European University Institute 3