This paper aims to give a historical example of internationalization and collaboration, which lasted for decades and gives an adequate example of contemporary trends that can be incorporated into courses. In the last third of the 18th century, the neighboring great powers divided Poland into three stages and deprived it of its independence until the end of the First World War, when Poland established itself as an independent state and regained its sovereignty in 1918. The leader of the newly established Poland, Józef Piłsudski, wanted to create a security alliance from the Baltic Sea to the Adriatic Sea after World War II. The North-South, Central, and Eastern European political project, which would have been based on the cooperation of independent states, could not be realized. Polish Foreign Minister Józef Beck renewed Piłsudski's plan in the second half of the 1930s. The idea of a federal state, known as the "third Europe", which he developed, was also not realized. In the second decade of the 21st century, the idea of political and economic cooperation between the Baltic, Adriatic, and the Black Sea states came to the fore again. Based on the Polish vision, the Three Seas Initiative, launched in 2016 at the initiative of Poland and Croatia, aims to strengthen regional cooperation, mainly in the fields of economy, energy policy, and security.