Luuk van der Baaren mentioned loss provisions were abolished.39 A novel provision was introduced in order to allow those who had lost Czech or Czechoslovak citizenship before the introduction of Act 186/2013 to reacquire their citizenship by declaration, although several categories of former citizens are excluded from this provision.40 In 2019, the provision was extended to children and grandchildren of former Czech or Czechoslovak citizens.41 Denmark Denmark has traditionally been intolerant towards dual citizenship. In 2011, a centre-left coalition came to power and announced that it intended to make Danish citizenship law less restrictive.42 Permitting dual citizenship was considered to be in line with that goal. Surprisingly, the right-wing Danish People’s Party, which had strongly opposed dual citizenship in the past, also came to support the toleration of dual citizenship as it would enable the revocation of citizenship from those who engage in or support terrorism.43 In 2014, an amending law to the Danish Citizenship Act was approved by the Danish Parliament, which subsequently came into force on 1 September 2015.44 The amending law abrogated several restricting provisions, namely a provision that required the renunciation of a foreign citizenship upon voluntary acquisition of Danish citizenship (Art. 4A Danish Citizenship Act), a provision on the automatic loss of Danish citizenship upon the voluntary acquisition of a foreign citizenship or entering public service abroad (Art. 7(i)(ii) Danish Citizenship Act), and provisions restricting dual citizenship for minors (Art. 5 par. 2 and Art. 7(iii) Danish Citizenship Act). Those who had lost Danish citizenship on the basis of the loss provisions in Art. 7 were enabled to reacquire Danish citizenship law by declaration between 1 September 2015 and 31 August 2020, except for those who had been unconditionally convicted to a custodial sentence during the period between the loss of Danish citizenship and the moment of making the declaration (Art. 3 Law No. 1497 of 23 December 2014). Estonia According to Art. 29 of the Estonian Citizenship, an Estonian national who acquires another citizenship is deemed to have ceased to be an Estonian citizen. A person who wishes to acquire Estonian citizenship by naturalisation is in principle required to provide a written confirmation that he or she has been released from his or her previous citizenship or will be released therefrom (Art. 19 par. 3 Citizenship Act). Estonian citizens who acquired another citizenship at birth are required to renounce one of their nationalities within three years after attaining the age of majority (Art. 3 Citizenship Act). Nevertheless, Art. 8 of the Estonian Constitution provides that Estonians citizens by birth cannot be deprived of their Estonian citizenship. Although it is clear that Estonian citizens by naturalisation are not permitted to hold more than one citizenship, it remains unclear whether this is also the case for citizens by birth who acquire 39 Act No. 186/2013 on Citizenship of the Czech Republic and on the amendment of selected other laws (the Czech Citizenship Act), via <https://www.globalcit.eu>. 40 Art. 31 Czech Citizenship Act. 41 Act. No. 207/2019, amending Act No. 186/2013 On Citizenship of the Czech Republic and on Amendments to Certain Acts (Act on Citizenship of the Czech Republic), via <https://www.globalcit.eu>. 42 Ersbøll, E., Report on citizenship law: Denmark, San Domenico di Fiesole: EUDO Citizenship Observatory 2015, p. 29. 43 Midtbøen, A.H., Roland Birkvad, S. and Bivand Erdal, M., Citizenship in the Nordic Countries: Past, Present Future, Temanord 2018, p. 35. 44 Law No. 1497 of 23 December 2014 amending the law on Danish citizenship, via <https://www.globalcit.eu>. RSCAS/GLOBALCIT-Comp. 2020/4 - © 2020 Authors 11