Central and Eastern Europe in the context of "Early Slavs"

The Pontic–Caspian Steppe is a steppe extending across Eastern Europe to Central Asia, formed by the Caspian and Pontic steppes. It stretches from the northern shores of the Black Sea (the Pontus Euxinus of antiquity) to the northern area around the Caspian Sea, where it ends at the Ural-Caspian narrowing, which joins it with the Kazakh Steppe in Central Asia, making it a part of the larger Eurasian Steppe. Geopolitically, the Pontic–Caspian Steppe extends from northeastern Bulgaria and southeastern Romania through Moldova, southern and eastern Ukraine, through the North Caucasus of southern Russia, and into the Lower Volga region where it straddles the border of southern Russia and western Kazakhstan. Biogeographically, it is a part of the Palearctic realm, and of the temperate grasslands, savannas, and shrublands biome.

The area corresponds to Cimmeria, Scythia, and Sarmatia of classical antiquity. Across several millennia, numerous tribes of nomadic horsemen used the steppe; many of them went on to conquer lands in the settled regions of Central and Eastern Europe, West Asia, and South Asia.

The Union of Soviet Socialist Republics (USSR), commonly known as the Soviet Union, was a transcontinental country that spanned much of Eurasia from 1922 until it dissolved in 1991. During its existence, it was the largest country by area, extending across eleven time zones and sharing borders with twelve countries, and the third-most populous country. An overall successor to the Russian Empire, it was nominally organized as a federal union of national republics, the largest and most populous of which was the Russian SFSR. In practice, its government and economy were highly centralized. As a one-party state governed by the Communist Party of the Soviet Union (CPSU), it was the flagship communist state. Its capital and largest city was Moscow.

The Soviet Union's roots lay in the October Revolution of 1917. The new government, led by Vladimir Lenin, established the Russian SFSR, the world's first constitutionally communist state. The revolution was not accepted by all within the Russian Republic, resulting in the Russian Civil War. The Russian SFSR and its subordinate republics were merged into the Soviet Union in 1922. Following Lenin's death in 1924, Joseph Stalin came to power, inaugurating rapid industrialization and forced collectivization that led to significant economic growth but contributed to a famine between 1930 and 1933 that killed millions. The Soviet forced labour camp system of the Gulag was expanded. During the late 1930s, Stalin's government conducted the Great Purge to remove opponents, resulting in large scale deportations, arrests, and show trials accompanied by public fear. Having failed to build an anti-Nazi coalition in Europe, the Soviet Union signed a non-aggression pact with Nazi Germany in 1939. Despite this, in 1941 Germany invaded the Soviet Union in the largest land invasion in history, opening the Eastern Front of World War II. The Soviets played a decisive role in defeating the Axis powers while liberating much of Central and Eastern Europe. However they would suffer an estimated 27 million casualties, which accounted for most losses among the victorious Allies. In the aftermath of the war, the Soviet Union consolidated the territory occupied by the Red Army, forming satellite states, and undertook rapid economic development which cemented its status as a superpower.

Budapest is the capital and most populous city of Hungary. It is Hungary's primate city with 1.7 million inhabitants and its greater metro area has a population of about 3.3 million, representing one-third of the country's population and producing above 40% of the country's economic output. Budapest is the political, economic, and cultural center of the country, among the ten largest cities in the European Union and the second largest urban area in Central and Eastern Europe. Budapest stands on the River Danube and is strategically located at the center of the Pannonian Basin, lying on ancient trade routes linking the hills of Transdanubia with the Great Plain.

Budapest is a global city, consistently ranked among the 50 most important cities in the world, belongs to the narrow group of cities with a GDP over US$100 billion, named a global cultural capital as having high-quality human capital, and is among the 35 most liveable cities in the world. The city is home to over 30 universities with more than 150,000 students, most of them attending large public research universities that are highly ranked worldwide in their fields, such as Eötvös Loránd University in natural sciences, Budapest University of Technology in engineering and technology, MATE in life sciences, and Semmelweis University in medicine. Budapest also hosts various international organizations, including several UN agencies, the WHO Budapest Centre, IOM regional centre, the EU headquarters of EIT and CEPOL, as well as the first foreign office of China Investment Agency. Budapest opened the first underground transit line on the European continent in 1896, which is still in use as M1 Millennium Underground, and today the fixed-track metro and tram network forms the backbone of Budapest's public transport system and transports 2.2 million people daily, making it a significant urban transit system.

The Warsaw Pact (WP), formally the Treaty of Friendship, Cooperation and Mutual Assistance (TFCMA), was a collective defense treaty signed in Warsaw, Poland, between the Soviet Union and seven other Eastern Bloc socialist republics in Central and Eastern Europe in May 1955, during the Cold War. The term "Warsaw Pact" commonly refers to both the treaty itself and its resultant military alliance, the Warsaw Pact Organisation (WPO) (also known as ‘Warsaw Treaty Organization’ (‘WTO’)). The Warsaw Pact was the military complement to the Council for Mutual Economic Assistance (Comecon), the economic organization for the Eastern Bloc states.

Dominated by the Soviet Union, the Warsaw Pact was established as a balance of power or counterweight to the North Atlantic Treaty Organization (NATO) and the Western Bloc. There was no direct military confrontation between the two organizations; instead, the conflict was fought on an ideological basis and through proxy wars. Both NATO and the Warsaw Pact led to the expansion of military forces and their integration into the respective blocs. The Warsaw Pact's largest military engagement was the Warsaw Pact invasion of Czechoslovakia, one of its own member states, in August 1968. All member states participated except for Albania and Romania, resulting in Albania's withdrawal from the pact less than one month later. The pact began to unravel with the spread of the Revolutions of 1989 through the Eastern Bloc, beginning with the Solidarity movement in Poland, its electoral success in June 1989 and the Pan-European Picnic in August 1989.

The Slavic languages, also known as the Slavonic languages, are Indo-European languages spoken primarily by the Slavic peoples and their descendants. They are thought to descend from a proto-language called Proto-Slavic, spoken during the Early Middle Ages, which in turn is thought to have descended from the earlier Proto-Balto-Slavic language, linking the Slavic languages to the Baltic languages in a Balto-Slavic group within the Indo-European family.

The current geographical distribution of natively spoken Slavic languages includes the Balkans, Central and Eastern Europe, and all the way from Western Siberia to the Russian Far East. Furthermore, the diasporas of many Slavic peoples have established isolated minorities of speakers of their languages all over the world. The number of speakers of all Slavic languages together was estimated to be 315 million at the turn of the twenty-first century. It is the largest and most diverse ethno-linguistic group in Europe.

The Eastern Bloc, also known as the Communist Bloc (Combloc), the Socialist Bloc, the Workers Bloc, and the Soviet Bloc, was an unofficial coalition of Communist states of Central and Eastern Europe, Asia, Africa, and Latin America that were aligned with the Soviet Union and existed during the Cold War (1947–1991). These states followed the ideology of Marxism–Leninism and various types of socialism, in opposition to the capitalist Western Bloc. The Eastern Bloc was often called the "Second World", whereas the term "First World" referred to the Western Bloc and "Third World" referred to the non-aligned countries that were mainly in Africa, Asia, and Latin America but notably also included former pre-1948 Soviet ally Yugoslavia, which was located in Europe.

In Western Europe, the term Eastern Bloc generally referred to the USSR and Central and Eastern European countries in the Comecon (East Germany, Poland, Czechoslovakia, Hungary, Romania, Bulgaria, and Albania). In Asia, the Eastern Bloc comprised Mongolia, Vietnam, Laos, Kampuchea, North Korea, South Yemen and China. In the Americas, the countries aligned with the Soviet Union included Cuba from 1961 and for limited periods Nicaragua and Grenada.

The removal of Hungary's border fence with Austria occurred in 1989 during the end of communism in Hungary, which was part of a broad wave of revolutions in various communist countries of Central and Eastern Europe. The border was still closely guarded and the Hungarian security forces tried to hold back refugees. The dismantling of the electric fence along Hungary's 240 kilometres (149 mi) long border with Austria was the first fissure in the "Iron Curtain" that had divided Europe for more than 40 years, since the end of World War II. Then the Pan-European Picnic caused a chain reaction in East Germany that ultimately resulted in the demise of the Berlin Wall.