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
