French nationality law

French nationality law is historically based on the principles of jus soli and jus sanguinis, according to Ernest Renan's definition, in opposition to the German definition of nationality, jus sanguinis, formalised by Johann Gottlieb Fichte.
The 1993 Méhaignerie Law, which was part of a broader immigration control agenda to restrict access to French nationality and increase the focus on jus sanguinis as the nationality determinant for children born in France, required children born in France of foreign parents to request French nationality between age 16 and age 21, rather than being automatically accorded citizenship at majority. This "manifestation of will" requirement was subsequently abrogated by the Guigou Law of 1998, but children born in France of foreign parents remain foreign until obtaining legal majority.
Children born in France to tourists or other short-term visitors do not acquire French nationality by virtue of birth in France: residency must be proven. Since immigration became increasingly a political theme in the 1980s, both left-wing and right-wing governments have issued several laws restricting the possibilities of access to French nationality.

Terminology

The distinction between the meaning of the terms citizenship and nationality is not always clear in the English language and differs by country. Generally, nationality refers to a person's legal belonging to a sovereign state and is the common term used in international treaties when addressing members of a country, while citizenship usually means the set of rights and duties a person has in that nation.
Historically, French nationals held differing sets of civil and political rights depending on their religion, ethnicity, economic standing, and sex. The right to vote in French elections did not extend to women, foreigners who naturalised as French nationals, colonial subjects, persons who were not required to pay property taxes, and members of non-Christian faiths. In this way, not all French nationals were necessarily full citizens.

History

In the society of the Ancien Régime, the rights of an individual depended on which social class they belonged to. The primary factor determining the privileges and obligations a person had was whether they were part of the nobility, clergy, or a higher socioeconomic level of the Third Estate. Foreigners who were not French subjects traditionally could not pass property to their descendants; the droit d'aubaine allowed the sovereign to confiscate the property of a resident alien in the event of their death. This confiscation became gradually less frequent through the early modern period, with an increasing amount of exceptions granted to foreign merchants to encourage their immigration into the country. France later negotiated treaties with many European states that exempted their subjects from this tax on a reciprocal basis in the latter half of the 18th century.
French nationality and citizenship were concepts that existed even before the French Revolution, loosely based on the premise that people spoke the same language within specific institutional frameworks.
Afterward, in the late 1700s and early 1800s, France was fairly unique among countries in tying its nationality laws to its election laws, and working to increase the joint ambit of citizenship and the right of the franchise.

19th century

There are three key dates in the legal history of naturalization:

Year	Event
1804	Civil Code, which allowed the possibility of naturalization.
1851	third generation immigrants were allowed to naturalize.
1889	second generation immigrants were allowed to naturalize once they reached the age of majority.

Soon after the approval of the French constitutions, statesman Jean-Jacques-Régis de Cambacérès drafted and presented a new civil code that would unify private law, including nationality law—and with application for all French citizens outside of France.

Third Republic

Military service and state education were two processes central to the creation of a common national culture. Military conscription brought inhabitants of the state's regions together for the first time, creating bonds of friendship and encouraging the use of French rather than regional languages. Universal education brought the whole of the population into contact with state-sanctioned version of French history and identity. State teachers, the "Black hussars of the Republic," conveyed the national language to the people of the regions.
In a series of expansions in the late 1800s, French nationality law was liberalized for great conferment of French citizenship, partly with an eye to increasing French military ranks. These included re-introduction of simple jus soli, elimination of the loss of citizenship when emigrating from France, and repeal of the loss of citizenship by a French woman on marriage to a foreigner when she did not automatically obtain her husband's citizenship.

20th century

In 1927, French nationality law was further loosened to increase naturalization so as to attract a larger work force for French industry. The measure also extracted the nationality law from the French civil code and made it an independent text, as it had grown too large and unwieldy.
Legislation in 1934, motivated by xenophobia, imposed burdens on naturalized citizens and provided the government powers to forfeit citizenship, which the Nazi-collaborator Vichy regime used widely.
A 1945 post-war measure promulgated a comprehensive nationality code that established very lengthy and detailed rules to shield citizens from government whimsy.
Amendments were by legislation in 1962 and by constitutions in 1946 and 1958, with the latter creating the status of "citoyen de la Communauté", vaguely akin to the British status of "Citizen of the United Kingdom and Colonies" established by the British Nationality Act 1948.
The 1993 law that attempted to restrict conferral of French citizenship also transferred the contents of the Code de la Nationalité Française back into the Code Civil, where they had existed from 1803 until 1927.

Denaturalization

According to Giorgio Agamben, France was one of the first European countries to pass denaturalization laws, in 1915, with regard to naturalized citizens of "enemy" origins. Its example was followed by most European countries.
As early as July 1940, Vichy France set up a special Commission charged with reviewing the naturalizations granted since the 1927 reform of the nationality law. Between June 1940 and August 1944, 15,000 persons, mostly Jews, were denaturalized. This bureaucratic designation was instrumental in their subsequent internment and murder.

Multiple citizenship

was officially recognized for both men and women on 9 January 1973; since then, possession of more than one nationality does not affect French nationality.
Before 19 October 1945, multiple nationality was prohibited and any French national who acquired another nationality before that day automatically lost French nationality unless they were male nationals under the obligation of military service and did not seek the release of their French nationality by decree. Until 1927, women who married a non-French national were also subject to the automatic loss of nationality if they acquired their husbands' nationalities upon marriage.
The 1945 French Nationality Code added a provision to indicate that for a maximum period of 5 years following the "legal cessation of hostilities", the permission for the loss of nationality must be sought from the French government if the person was male and under the age of 50. The transitional period was deemed to have ended on 1 June 1951. Also, the new code specified that a woman would lose her French nationality only when she declared that she did not want to remain French after marriage.
The 1954 amendment to the Nationality Code removed the five-year period and, retroactively from 1 June 1951, no male national of France under the age of 50 would be subject to the automatic loss provision of the 1945 Nationality Code without the specific permission from the French government. This limited the automatic loss of nationality to men over 50 and women, as the permissions to lose French nationality were automatically given to them upon their naturalizations. In 2013, a woman who lost her French nationality under section 87 appealed to the Constitutional Council, which found the provision to be unconstitutional under the 1946 Constitution and the 1789 Declaration and ordered the reinstatement of her nationality. As a result of this decision, all women who lost their nationality between 1951 and 1973 solely under section 87 may voluntarily request for the reinstatement of their nationality by invoking this decision, and their descendants would also be able to invoke this decision if their female ancestors have done so.
Since 1973, dual nationality has been legalized for all French nationals, although a person might still be deprived of their French nationality under bilateral or multilateral treaties or agreements France concluded with other countries. In 2007, the Ministry of Justice concluded that a French male residing in the Netherlands and naturalized as a Dutch national in 2006 based on his marriage to a Dutch man lost his French nationality upon naturalization, because a 1985 agreement between France and the Netherlands stipulated that any national of either country who acquired the other country's nationality would cease to be a national of their country of origin. A provision in the agreement provided exemptions for married couples, but as France did not recognize same-sex marriage in 2006, it was deemed to be not applicable to him as he was not considered to be married under French law.
Due to the case which sparked national outrage, the Sarkozy administration announced that it would be taking steps to denounce some portions in the agreements with the Netherlands and other countries in 2009. France later denounced Chapter I of the Council of Europe's Convention on the Reduction of Cases of Multiple Nationality and on Military Obligations in Cases of Multiple Nationality of May 6, 1963. The denunciation took effect on March 5, 2009.