Segurança da Fronteira Oriental da União Europeia. Os Aspectos Político-Jurídicos

When Russia launched a wide-scale invasion of Ukraine in February 2022, it became obvious to the entire European Union that the Russian Federation posed one of the most serious threats to the entire region, including the European Union. Therefore, the countries of the EU's eastern flank have undertaken initiatives to strengthen the defence system of their eastern borders forming also the EU's eastern border. Based on the following methods: legal dogmatic method, legal theoretical method, comparative method, systemic method, qualitative and quantitative analyses supplemented by a historical approach, the article analyses the current security environment of the Baltic States and Poland (as European Union countries). This allowed us to understand the motives behind undertaking the East Shield and Baltic Defence Line initiatives. The main purpose of the article is to analyse the evolution of the European Union's approach to the security of its eastern external border, with particular emphasis on investments in defence infrastructural projects in the Baltic States and Poland.