East Germany in the context of "Reunified Germany"

The revolutions of 1989, also known as the fall of communism, were a wave of liberal democratic movements that resulted in the collapse of most Marxist–Leninist governments in the Eastern Bloc and other parts of the world. This wave is sometimes referred to as the "autumn of nations", in reference to the revolutions of 1848 as the "spring of nations". The revolutions of 1989 were a key factor in the dissolution of the Soviet Union—one of the two superpowers—and abandonment of communist regimes in many parts of the world, some of which were violently overthrown. These events drastically altered the world's balance of power, marking the end of the Cold War and beginning of the post-Cold War era.

The earliest recorded protests, which led to the revolutions, began in Poland on 14 August 1980, the massive general strike which led to the August Agreements and establishment of Solidarity, the first and only independent trade union in the Eastern Bloc, whose peak membership reached 10 million. The main region of the 1989 revolutions was Central Europe, starting in Poland with the 1988 Polish strikes, and continued in Hungary, East Germany, Bulgaria, Czechoslovakia, and Romania. On 4 June 1989, Poland conducted the first elections that led to the dissolution of the communist government, with Solidarity winning an overwhelming victory, leading to the peaceful fall of communism in Poland. Influenced by Poland, Hungary organised round table-format talks and began dismantling its section of the Iron Curtain. In August 1989, over a quarter of the Baltic states population physically chained for 675 kilometres (419 mi) in the Baltic Way protesting the occupation by the Soviet Union, while the opening of a border gate between Austria and Hungary set in motion a peaceful chain reaction, in which the Eastern Bloc disintegrated. This led to mass demonstrations in cities of East Germany and the fall of the Berlin Wall in November 1989, which served as the symbolic gateway to German reunification in 1990. A feature common to these developments was the extensive use of campaigns of civil resistance, demonstrating popular opposition to the continuation of one-party rule and contributing to pressure for change. Romania was the only country in which citizens and opposition forces used violence to overthrow its communist regime, although Romania was politically isolated from the rest of the Eastern Bloc.

A steam engine is a heat engine that performs mechanical work using steam as its working fluid. The steam engine uses the force produced by steam pressure to push a piston back and forth inside a cylinder. This pushing force can be transformed by a connecting rod and crank into rotational force for work. The term "steam engine" is most commonly applied to reciprocating engines as just described, although some authorities have also referred to the steam turbine and devices such as Hero's aeolipile as "steam engines". The essential feature of steam engines is that they are external combustion engines, where the working fluid is separated from the combustion products. The ideal thermodynamic cycle used to analyze this process is called the Rankine cycle. In general usage, the term steam engine can refer to either complete steam plants (including boilers etc.), such as railway steam locomotives and portable engines, or may refer to the piston or turbine machinery alone, as in the beam engine and stationary steam engine.

Steam-driven devices such as the aeolipile were known in the first century AD, and there were a few other uses recorded in the 16th century. In 1606 Jerónimo de Ayanz y Beaumont patented his invention of the first steam-powered water pump for draining mines. Thomas Savery is considered the inventor of the first commercially used steam powered device, a steam pump that used steam pressure operating directly on the water. The first commercially successful engine that could transmit continuous power to a machine was developed in 1712 by Thomas Newcomen. In 1764, James Watt made a critical improvement by removing spent steam to a separate vessel for condensation, greatly improving the amount of work obtained per unit of fuel consumed. By the 19th century, stationary steam engines powered the factories of the Industrial Revolution. Steam engines replaced sails for ships on paddle steamers, and steam locomotives operated on the railways.

The European Green Belt initiative is a grassroots movement for nature conservation and sustainable development along the corridor of the former Iron Curtain. The term refers to an environmental initiative as well as the area it concerns. The initiative is carried out under the patronage of the International Union for Conservation of Nature and formerly Mikhail Gorbachev. It is the aim of the initiative to create the backbone of an ecological network that runs from the Barents to the Black and Adriatic Seas.

The European Green Belt as an area follows the route of the former Iron Curtain and connects national parks, nature parks, biosphere reserves and transboundary protected areas as well as non-protected valuable habitats along or across the (former) borders.

The 1992 Winter Olympics, officially known as the XVI Olympic Winter Games (French: XVI Jeux Olympiques d'hiver) and commonly known as Albertville '92 (Arpitan: Arbèrtvile '92), were a winter multi-sport event held from 8 to 23 February 1992 in and around Albertville, France. Albertville won the bid to host the Winter Olympics in 1986, beating Sofia, Falun, Lillehammer, Cortina d'Ampezzo, Anchorage, and Berchtesgaden. The 1992 Winter Olympics were the last winter games held in the same year as the Summer Olympics. The next Winter Olympics were held two years after this one instead of the usual four, which allowed the Olympic Games to take place on every even-numbered year instead of every four years. The Games were the fifth Olympic Games held in France and the country's third Winter Olympics, after the 1924 Winter Games in Chamonix and the 1968 Winter Games in Grenoble. This games was the first of two consecutive Olympic games to be held in Western Europe, preceding the 1992 Summer Olympics in Barcelona, Spain.

18 events in Figure skating, short track speed skating, speed skating, and the opening and closing ceremonies took place in Albertville. The 39 other events were held in the nearby 9 villages and resorts around Savoie: Courchevel, La Plagne, Les Arcs, Les Menuires, Les Saisies, Méribel, Pralognan-la-Vanoise, Tignes, and Val d'Isère. Sixty-four National Olympic Committees and 1,801 athletes participated in six sports and fifty-seven events. This included both the Unified Team, representing the non-Baltic former Soviet republics, and Germany, newly consolidated again as a team following the reunification of the former East and West Germany in 1990. The event also saw the debut of eight nations in the Winter Olympics. The Winter Olympic program has grown this time with the addition of 11 new events. While sports that were already on the program received 5 new events (2 new events in cross-country skiing, at the same time women were allowed to compete in biathlon for the first time and won 3 events exclusive to them.) Another 6 events were added with the implementation of 2 sports that were demonstrated 4 years earlier (freestyle skiing and short track speed skating). These were the last Winter Olympics to include demonstration sports, consisting of curling, aerials and ski ballet, and speed skiing. Due to a rule change implemented in 1986, this was the last edition in the history of the Winter Olympic Games in which all speed skating events were held in an open-air venue.

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 Polish People's Republic (1952–1989), formerly the Republic of Poland (1947–1952), and also often simply known as Poland, was a country in Central Europe that existed as the predecessor of the modern-day democratic Republic of Poland. With a population of approximately 37.9 million near the end of its existence, it was the second most-populous communist and Eastern Bloc country in Europe. It was also where the Warsaw Pact was founded. The largest city and capital was Warsaw, followed by the industrial city of Łódź and cultural city of Kraków. The country was bordered by the Baltic Sea to the north, the Soviet Union to the east, Czechoslovakia to the south, and East Germany to the west.

The Polish People's Republic was a unitary communist state established in the country after the Red Army's takeover of Polish territory from German occupation in World War II. Communist control was strengthened through electoral fraud in the 1946 Polish people's referendum and the 1947 Polish parliamentary election. The Polish United Workers' Party (PZPR) became the dominant political faction in a one-party state, but the country had more liberal policies than other socialist states due to its strategic location in the Cold War and internal opposition. The state's official name was the "Republic of Poland" (Rzeczpospolita Polska) between 1947 and 1952 in accordance with the temporary Small Constitution of 1947. The name "People's Republic" was introduced and defined by the Constitution of 1952. The Polish People's Republic was dissolved following the Revolutions of 1989 and the 1990 Polish presidential election, but the post-communist Third Polish Republic retained the 1952 constitution, with amendments, until the introduction of the current constitution on 17 October 1997, abolishing the socialist structure entirely and replacing it with a parliamentary system that has remained in place to the present-day.

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.

German reunification (German: Deutsche Wiedervereinigung), also known as the expansion of the Federal Republic of Germany (BRD), was the process of re-establishing Germany as a single sovereign state, which began on 9 November 1989 and culminated on 3 October 1990 with the dissolution of the German Democratic Republic and the integration of its re-established constituent federated states into the Federal Republic of Germany to form present-day Germany. This date was chosen as the customary German Unity Day, and has thereafter been celebrated each year as a national holiday. On the same date, East and West Berlin were also reunified into a single city, which eventually became the capital of Germany.

The East German government, controlled by the Socialist Unity Party of Germany (SED), started to falter on 2 May 1989, when the removal of Hungary's border fence with Austria opened a hole in the Iron Curtain. The border was still closely guarded, but the Pan-European Picnic and the indecisive reaction of the rulers of the Eastern Bloc started off an irreversible movement. It allowed an exodus of thousands of East Germans fleeing to West Germany via Hungary. The Peaceful Revolution, part of the international revolutions of 1989 including a series of protests by East German citizens, led to the fall of the Berlin Wall on 9 November 1989 and the GDR's first free elections on 18 March 1990, and then to negotiations between the two countries that culminated in a Unification Treaty. Other negotiations between the two Germanies and the four occupying powers in Germany produced the Treaty on the Final Settlement with Respect to Germany, which granted on 15 March 1991 full sovereignty to a reunified German state, whose two parts had previously been bound by a number of limitations stemming from their post-World War II status as occupation zones, though it was not until 31 August 1994 that the last Russian occupation troops left Germany.

Law enforcement in Germany is constitutionally vested solely with the states, which is one of the main features of the German political system.

Policing has always been a responsibility of the German states even after 1871 when the country was unified. The 1919 constitution of the Weimar Republic did provide for the possibility of creating a national police force, should the necessity arise, but it was only in the Nazi era that Gestapo (Secret State Police) were unified under central control and a national police force created (the Reich Security Main Office—Reichssicherheitshauptamt, or RSHA). The police became a tool of the centralized state and the Nazi party.Following the defeat of 1945, Germany was divided; in 1949 the three western zones were turned into the new West Germany, while the Soviet zone became East Germany. Each country pursued a different path concerning law enforcement.