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— CH. 1 · THE WAR THAT SHOOK ALLEGIANCE —

Multiple citizenship

~6 min read · Ch. 1 of 6
6 sections
  • In 1812, British naval officers boarded American ships and dragged sailors into service. These men had been born in the United States but were claimed as subjects of Great Britain because they were born on British soil or to British parents. The conflict arose from a legal doctrine called perpetual allegiance, which held that a person could never truly leave their country of origin. This belief created diplomatic chaos when millions of people began migrating across oceans during the nineteenth century.

    The situation escalated after the War of 1812 ended. Irish-born Americans traveled back to Ireland to join the Fenian Rising in 1867. British authorities arrested them for treason, arguing that their birth made them British subjects regardless of their new American citizenship. The outrage among Irish-Americans forced the United Kingdom to reconsider its stance. Congress responded by passing the Expatriation Act of 1868, granting Americans the right to freely renounce their US citizenship. The UK followed suit in 1870, allowing British subjects who naturalized as US citizens to lose their British nationality.

    President Ulysses S. Grant addressed this issue in his State of the Union address in 1874. He decried individuals claiming the benefits of citizenship while living abroad without intending to return. The US government negotiated agreements known as the Bancroft Treaties between 1868 and 1937. These treaties pledged signatories to treat voluntary naturalization with another sovereign nation as a renunciation of previous citizenship.

  • Citizenship laws vary significantly around the world, creating situations where a person holds multiple nationalities simultaneously. Jus sanguinis allows countries to grant citizenship based on descent from parents or grandparents. Most modern nations trace citizenship through either parent, extending rights even to children born outside the country's borders.

    Jus soli grants unconditional birthright citizenship to anyone born within a territory. The United States, Canada, and many Latin American countries practice this principle. Australia, France, Germany, Ireland, New Zealand, South Africa, and the UK have modified jus soli rules requiring at least one parent to be a citizen or legal permanent resident.

    Some countries offer citizenship by marriage, though few grant it automatically on the wedding day. Iran is an exception that provides immediate citizenship upon marriage. Other nations revoke spousal citizenship if the marriage ends within a specified timeframe, such as Algeria does.

    Investment programs allow individuals to obtain citizenship through substantial monetary contributions. Five Caribbean nations including Antigua and Barbuda, Grenada, Dominica, Saint Kitts and Nevis, and Saint Lucia offer these programs. Vanuatu, Montenegro, Turkey, and Jordan also provide citizenship by investment options. Portugal offers a residence program with a five-year timeline before eligibility for citizenship.

  • Nations enforce restrictions differently when dealing with dual citizens. Austria permits dual citizenship only for those who obtained another citizenship by birth. Germany restricted dual citizenship until the 27th of June 2024, when new legislation allowed all cases of dual nationality without requiring renunciation of previous citizenship.

    Spain maintains dual citizenship treaties with Argentina, Bolivia, Chile, Colombia, Costa Rica, Dominican Republic, Ecuador, Honduras, Guatemala, Nicaragua, Paraguay, Peru, Puerto Rico, and Venezuela. Spaniards residing in these territories do not lose their rights as Spaniards if they adopt that nationality. For other countries, Spanish citizenship is lost three years after acquiring foreign citizenship unless declared otherwise.

    South Africa required citizens to apply for permission from the Minister of Home Affairs before acquiring another country's citizenship. The Supreme Court of Appeal struck down this requirement on the 13th of June 2023, ordering reinstatement of citizenship for those who lost it under the old rules. Pakistan allows dual citizenship with twenty countries including Australia, Canada, France, Germany, Ireland, Italy, New Zealand, Sweden, Switzerland, Syria, the United Kingdom, and the United States.

    Turkey requires citizens applying for another nationality to inform Turkish officials and provide original naturalization certificates. Dual nationals are not compelled to use a Turkish passport to enter or leave Turkey but must show their Turkish national ID card.

  • Switzerland operates a three-tier system of citizenship involving Confederation, canton, and commune levels. People from Åland possess joint regional and Finnish citizenship. Ålanders can buy property and set up businesses on the islands, while Finns without regional citizenship cannot obtain these privileges.

    The Crown Dependencies of Jersey, Guernsey, and Isle of Man have local legislation restricting employment and housing rights to those with local status. British Overseas Territories maintain concepts of belonger status alongside existing British citizenship. Citizens of Hong Kong and Macau Special Administrative Regions hold permanent resident status tied to household registration systems in mainland China.

    Bosnia and Herzegovina grants citizens entity-level citizenship of either Republika Srpska or Federation of Bosnia and Herzegovina depending on residence. Malaysia's thirteen states provide benefits like baby bonuses and education loans to children born within state boundaries. Sabah and Sarawak maintain independent immigration control systems separate from Peninsular Malaysian states.

    People from Cook Islands and Niue hold New Zealand citizenship along with local status not extended to other New Zealanders. The territorial government of Puerto Rico began issuing citizenship certificates in September 2007 following a court victory by Juan Mari Brás validating claims for anyone born on the island.

  • Dual citizens face barriers when seeking public office or security clearances. Section 44(i) of Australia's Constitution explicitly forbids individuals holding allegiance to foreign powers from sitting in parliament. Senator-elect Heather Hill was disqualified because she was subject to a foreign power at election time, though dual citizenship alone does not automatically disqualify candidates.

    In Israel, certain military units including the Navy's submarine fleet require candidates to renounce any other citizenship before joining. Some combat units allow declaration but not renunciation of foreign citizenship. The case of Ben Zygier sparked debate about dual citizenship among Australian politicians.

    Arnold Schwarzenegger retained Austrian citizenship during his service as Governor of California while US Senator Ted Cruz renounced Canadian citizenship birthright on the 14th of May 2014. David McAllister held British and German citizenship while serving as minister president of Lower-Saxony from the 1st of July 2010 to the 19th of February 2013.

    Michaëlle Jean renounced French citizenship two days before taking office as Governor General of Canada despite controversy surrounding her marriage to French-born filmmaker Jean-Daniel Lafond. Former Canadian Prime Minister John Turner remained born in the United Kingdom while retaining dual citizenship.

  • A 2007 study published in The Journal of Politics examined whether allowing dual citizenship impedes cultural assimilation or social integration. Stanley Renshon wrote for the Center for Immigration Studies citing rising tension between mainstream and migrant communities as evidence needing strong national identity maintenance.

    The same academic research found dual citizens were 32% less likely to be fluent in English and 18% less likely to identify as American compared to single citizens. They were also 19% less likely to consider the US their homeland and 15% less likely to have ever voted in a national election.

    Research indicates these effects appear limited almost exclusively to first-generation immigrants according to data available at the time. A full assessment beyond the first generation remains impossible with current information. Proponents argue dual citizenship encourages political activity providing avenues for immigrants unwilling to forsake countries of origin due to loyalty or separation feelings.

    The United States represents a civic nation model where citizenship depends on political loyalty rather than ethnicity. This makes it imperative that immigrants assimilate into the greater whole since no ethnic cohesiveness unites the populace. Countries following the differential exclusionary model accept temporary guestworkers but remain highly restrictive regarding naturalization.

Common questions

When did the United States pass the Expatriation Act of 1868?

The United States passed the Expatriation Act of 1868 to grant Americans the right to freely renounce their US citizenship. This legislation followed diplomatic conflicts involving British naval officers boarding American ships in 1812 and claiming sailors as subjects of Great Britain.

What is the difference between jus sanguinis and jus soli citizenship laws?

Jus sanguinis allows countries to grant citizenship based on descent from parents or grandparents regardless of birth location. Jus soli grants unconditional birthright citizenship to anyone born within a territory, though Australia, France, Germany, Ireland, New Zealand, South Africa, and the UK have modified these rules requiring at least one parent to be a citizen or legal permanent resident.

Which countries allow dual citizenship through investment programs?

Five Caribbean nations including Antigua and Barbuda, Grenada, Dominica, Saint Kitts and Nevis, and Saint Lucia offer citizenship by investment programs. Vanuatu, Montenegro, Turkey, and Jordan also provide citizenship by investment options while Portugal offers a residence program with a five-year timeline before eligibility for citizenship.

When did Germany change its laws regarding dual nationality?

Germany restricted dual citizenship until the 27th of June 2024 when new legislation allowed all cases of dual nationality without requiring renunciation of previous citizenship. Austria permits dual citizenship only for those who obtained another citizenship by birth.

How does Spain handle dual citizenship treaties with Latin American countries?

Spain maintains dual citizenship treaties with Argentina, Bolivia, Chile, Colombia, Costa Rica, Dominican Republic, Ecuador, Honduras, Guatemala, Nicaragua, Paraguay, Peru, Puerto Rico, and Venezuela. Spaniards residing in these territories do not lose their rights as Spaniards if they adopt that nationality but Spanish citizenship is lost three years after acquiring foreign citizenship unless declared otherwise.

All sources

170 references cited across the entry

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  11. 43harvnbSpanish Civil Code
  12. 47webSouth Korea: Permanent Dual Nationality Allowed after 60 YearsThe Library of Congress — August 24, 2010
  13. 62bookDual Citizenship in Global Perspective: From Unitary to Multiple CitizenshipHoundmills, UK: Palgrave Macmillan — November 2007
  14. 64newsUAE to allow dual citizenshipAshleigh Stewart — January 30, 2021
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  16. 68webRules of Swiss citizenshipSwiss Government
  17. 69webIntroduction to Dual CitizenshipAustralian Government
  18. 70news申请赴香港、澳门定居定居须知Xianyou County Government — 2009-08-07
  19. 72webRight of domicile in ÅlandParliament of Åland
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  27. 100newsNo, Canada: Sen. Ted Cruz has formally shed his dual citizenshipTodd Gillman — A. H. Belo — June 10, 2014
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  38. 120newsAn American Tax NightmareStu Haugen — May 13, 2015
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  40. 122webMexican Nationality Law, Article XIVSecretariat of Foreign Affairs
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  42. 130webReport on Citizenship Law: TasmaniaCaroline Nalule et al. — European University Institute — April 2020
  43. 140webVietnam to allow dual nationalityFrank Zeller — 14 November 2008
  44. 143webGeneral Information on Chinese NationalityImmigration Department, Government of the Hong Kong SAR
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  48. 150webOverseas Citizenship of India SchemeThe Ministry of Overseas Indian Affairs — May 31, 2013
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  50. 157bookDual Nationality, Social Rights and Federal Citizenship in the U. S. and Europe: The Reinvention of CitizenshipBerghahn Books — 2002
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