During the occupation and subsequent annexation of the Crimean peninsula, the Russian Federation announced all Ukrainian nationals living in Crimea its subjects. Residents of the occupied territory faced a difficult choice. On the one hand, by obtaining Russian passports, they formally took the oath of allegiance to the State which had committed an act of aggression against their sovereign-country. On the other hand, during a short period of time (in fact - 18 days) they could try to submit the “declaration about the willingness to retain the nationality of Ukraine” to one of the four offices which accepted such declarations in Crimea. In this case, they suddenly became foreigners at home and were severely limited in their rights. Using the imperfection of international standards in this ng situations of statelessness and resolving cases of dual nationality. Arbitrary change and imposition of a nationality became a new challenge to which the world was not ready. Having imposed its nationality, the Russian Federation «forced into loyalty» the population of the occupied peninsula under threat of criminal liability (see. Art. 275 of the Criminal Code «High Treason»).