For a long time, the laws and legal policies regulating the matter of Polish citizenship have equated the acquisition of citizenship from another country or service in a foreign army with the loss of Polish citizenship. However, this is not a unique system only known to Polish law. Currently, many countries, such as China, do not allow for dual citizenship. Enlisting in a foreign army is often similarly treated as a renunciation of loyalty to one’s country of origin and leads to revocation of citizenship. In the case of Poland, these currently are not obstacles, while in the past, citizenship was only revoked during specific years and circumstances.

The first regulation in the 20th century regarding the acquisition, as well as loss, of Polish citizenship is the Polish Citizenship Act of January 20, 1920, which went into effect on January 31, 1920. Importantly, the law in question is still applied in the procedure of acquiring Polish citizenship through its confirmation. This act, along with later acts, are applied to determine the acquisition, possession and retention of Polish citizenship of individuals to whom they are applicable to in the specified period.

What should we know about this law?

First, it was very stringent. A Polish citizen could lose their Polish citizenship if they acquired foreign citizenship, or if they took up a public office or enlisted in military service in a foreign state without the consent of the Polish Government, while a female Polish citizen could lose her citizenship if she married a foreigner.

It should be emphasized, however, that not everyone who acquired foreign citizenship or enlisted in military service in a foreign country between January 31, 1920 and January 19, 1951, consequently lost their Polish citizenship as a result.

Pursuant to the Polish Citizenship Act of January 20, 1920, “individuals subject to a military draft may acquire foreign citizenship only after obtaining permission from the Minister of Military Affairs, otherwise they will not cease to be considered Polish citizens by the Polish State.” In practice, this means that men of recruitment age, without the consent of the Minister of the Interior to take up service in a foreign army, did not lose Polish citizenship. Of course, the recruitment age had changed over the period of time when the law was in place, due to successive amendments to the law regarding general military service.

Another extremely important issue is taking up service in the army of a foreign country. As was already mentioned, this was not always tantamount to the loss of Polish citizenship. Let us remember that at the time that the Polish Citizenship Act of January 20, 1920 was in effect, World War II had broken out. According to the established position of the Polish judicature, enlisting in military service in a foreign country during the realities of World War II did not result in the loss of Polish citizenship, moreover, the official end of the war could not mean that continued service, after the date established as the end of the war, on that day resulted in the loss of Polish citizenship.

Responding to one of the questions frequently asked by our clients, unlike the Polish Citizenship Act of January 20, 1920, the Polish Citizenship Act of January 8, 1951, which entered into effect on January 19, 1951, as well as the subsequent acts, did not implement the loss of Polish citizenship in the event of acquiring foreign citizenship without the permission of the Polish authorities or enlisting in military service in a foreign country without the consent of the Polish Government.

In cases of loss of citizenship due to marriage with a foreign citizen, whether the marriage was civil or religious may be an important factor. Many times, especially among people of Jewish origin, weddings were held exclusively through a religious ceremony without subsequent registration with the registry office. Depending on the circumstances, in some cases this works to the benefit of the person applying for confirmation of citizenship. Similarly significant may be the parent’s registering a child with the registry office, which was equivalent to legal recognition of the child. At the time, even the lack of a civil marriage resulted in the acquisition of citizenship of the father, so long as the father registered the child with the registry office.

Apl. Adw. Aleksandra ZakrzewskaApl. Adw. Aleksandra Zakrzewska

Attorney Apprentice in Warsaw Bar Association. Specializes in obtaining and confirming polish citizenship, civil process, and US immigration law.





Jarosław KurpiejewskiJarosław Kurpiejewski

Attorney at Law licensed in Poland. Senior Associate in Ilasz & Associates Law Firm in New York. Specializes in private international law, civil litigation and immigration law.



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