Shifts in power in Eastern Europe have been a central topic in global political analysis over the past few decades. Since the collapse of the Soviet Union in 1991, the region has undergone significant transformation, affecting international relations as well as regional stability. After this period, Eastern European countries sought to build national identities and sought new affiliations, especially with the European Union and NATO. One of the key factors in this shift in power is the rise of populism and nationalism in various countries. This was clearly visible in elections in Poland, Hungary and Slovakia, where populist parties dominated the political scene. Using anti-immigration rhetoric and nihilism against liberal elites, they succeeded in attracting the sympathy of many voters. In Hungary, Viktor Orbán succeeded in strengthening his power through controversial legal reforms, including controlling the media and reducing the independence of the judiciary. On the other hand, Russia under Vladimir Putin is trying to maintain its influence in Eastern Europe. Its aggressive foreign policy, including its annexation of Crimea in 2014 and its support for separatists in eastern Ukraine, created ongoing tensions. Russia also uses energy as a political tool, threatening countries that seek to move away from Moscow’s influence. In the midst of this dynamic, the Baltic region, including Estonia, Latvia and Lithuania, is trying to build stronger defenses with NATO support. This defensive policy was motivated by fear of a potential Russian invasion, encouraging closer military cooperation between these countries and western partners. The economic transition also contributed to the shift in power in Eastern Europe. Although these countries have experienced growth, inequality of prosperity and corruption remain. Economic reform and efforts to attract foreign investment were top priorities, but internal problems often hampered progress. Many countries are still struggling with the impact of the legacy of communist rule that created dependency on certain industries. Changes in the social and demographic climate also play an important role. Migration from Eastern European countries to Western Europe in search of better opportunities has created labor shortages in several sectors. This has had an impact on the rise of pro-immigration movements in countries receiving migrant flows, changing local political dynamics. The influence of the European Union remains a crucial factor in this shift in power. Although some countries are trying to move closer to European democratic values, there are tensions that arise from societies skeptical of outside influence. The situation in Ukraine, which is facing war with the support of pro-Russian separatist groups, shows how complex the situation on the ground is when pro-western aspirations and Russian influence converge. Working together in a regional security context is important. Meetings such as the Baltic Defense Cooperation Center demonstrate efforts to consolidate defense strategy. In addition, economic cooperation is also experiencing development, with various initiatives aimed at strengthening relations between Eastern European countries, creating a more solid regional bloc. Civil society has also played a role in this shift, with many NGOs advocating for reform and transparency. This creates space for open dialogue and strengthens democratic principles, although it is often faced with challenges from authoritarian governments that seek to silence criticism. Shifts in power in Eastern Europe demonstrate a complex interaction between domestic and international factors. Taking these dynamics into account, the future of Eastern Europe remains filled with challenges and opportunities, redefining international relations in the modern era.