The term Central and Eastern Europe (CEE) is a geopolitical concept encompassing countries in Central Europe, Eastern Europe, and Southeast Europe, primarily defined by their shared history as former communist states. The region includes countries like Poland, Hungary, the Czech Republic, Slovakia, the Baltic states (Estonia, Latvia, Lithuania), and the Balkan states. The Organisation for Economic Co-operation and Development (OECD) uses the term Central and Eastern European Countries (CEECs) for a group including Albania, Bulgaria, Croatia, the Czech Republic, Hungary, Poland, Romania, the Slovak Republic, Slovenia, and the three Baltic States.
The concept originated after the collapse of the Eastern Bloc and the end of the Cold War in the late 1980s. The problem it solved was the need for a collective term to describe the countries undergoing a radical transition from communist rule to democratic political structures and market economies. Historically, the region was situated between the Russian Empire and the Holy Roman Empire or Austro-Hungary.
The key mechanism of the CEE transition was the shift to advanced market economies, which the World Bank considered complete for many countries by 2008. A major connecting factor is the European Union (EU), which many CEE countries joined in waves: eight countries joined on May 1, 2004, two on January 1, 2007, and Croatia on July 1, 2013. The region is also connected to the Three-Seas Initiative, a regional alliance founded by Poland and Croatia in August 2016 to integrate infrastructure between the Baltic, Adriatic, and Black Seas.
The region's geopolitical status has changed recently due to Russia's war in Ukraine, which has caused divergent economic growth trajectories and a starker division between the EU-led bloc and the former Soviet Union (excluding the Baltics). However, the core mechanism of economic integration with the EU, including a large share of trade passing through global value chains with the euro area, has remained a defining feature.