The effects of enlargement on European Union citizenship

Abstract The enlargement of the European Union (EU) is a complicated and multifaceted process that has been shaping the legal landscape of the Union to a considerable degree. It has many dimensions, but there is a specific one that rarely comes into the academic spotlight. This article analyses the effects of enlargement on Union citizenship. The piece sheds light on the specific ways EU citizenship is influenced and transformed by the accession of new Member States from the legal perspective, focusing on the personal scope of Union citizenship, the territorial reach of EU citizens’ rights, and the EU law control over the nationality policies of the Member States. The piece also presents the concept of transitional EU citizenship as a more nuanced way of understanding how enlargement not simply limits the right to free movement of the nationals of the newly acceded countries but rather fractures the freedom of movement as such across the Union. This article argues that the enlargement of the Union has considerable effects on EU citizenship that are, however, two-fold: Although the accession of new Member States expands the Union citizenship status in many ways, it also significantly threatens EU citizenship’s coherence, functionality, and integrity as a legal status.