Why did the Cold War come to an end?

The Cold War ended chiefly because of the decline of the Soviet Union. Its command economy was inefficient and could not match Western living standards, and it was burdened by heavy military spending, the cost of the arms race intensified under the United States in the 1980s, and the strain of controlling Eastern Europe. Gorbachev's reforms of glasnost and perestroika failed to revive the economy and instead loosened control, leading to the collapse of communism in Eastern Europe in 1989 and the disintegration of the Soviet Union in 1991. The strongest explanation weighs internal Soviet weakness, Gorbachev's choices and Western pressure together.

What was detente and how successful was it?

Detente was the easing of Cold War tension between the superpowers in the 1970s, marked by arms-control agreements and improved relations. It reduced the immediate danger of nuclear war and produced agreements limiting weapons, which was a real achievement. However, it did not end the underlying rivalry, and tension rose again at the end of the 1970s and into the 1980s. So detente was a partial success: it eased tension for a time but did not resolve the fundamental conflict, which is why it is best seen as a phase rather than the end of the Cold War.

What were glasnost and perestroika?

These were Gorbachev's two main reform policies in the Soviet Union. Glasnost meant 'openness', allowing more freedom of speech and criticism of the system to expose problems. Perestroika meant 'restructuring', an attempt to reform and modernise the inefficient command economy. Gorbachev hoped to revive the Soviet Union, but the reforms failed to fix the economy and instead encouraged demands for greater change, weakened the Communist Party's control and helped unleash the forces that ended communist rule in Eastern Europe and broke up the Soviet Union.

Why did communism collapse in Eastern Europe in 1989?

Communism collapsed across Eastern Europe in 1989 because the Soviet Union, under Gorbachev, made clear it would no longer use force to keep the satellite states in line, removing the fear that had held the system together. Years of economic failure and resentment of communist rule meant that, once Soviet backing was withdrawn, popular movements swept the communist governments aside, mostly peacefully. The fall of the Berlin Wall in November 1989 became the great symbol of this collapse and of the end of the division of Europe.

Why was the fall of the Berlin Wall so significant?

The Berlin Wall, built in 1961 to stop East Germans fleeing to the West, had become the most powerful symbol of the divided Cold War world. Its fall in November 1989 showed that communist control of Eastern Europe had collapsed and that the Soviet Union would not intervene to save it. It opened the way to German reunification and signalled, more clearly than any other event, that the Cold War division of Europe was ending. For that reason it is treated as the symbolic end of the Cold War in Europe.

SingaporeHistory

The end of the Cold War: detente, Gorbachev's reforms, the fall of the Berlin Wall and the collapse of the Soviet Union for O-Level Elective History

A module overview of the end of the Cold War for Singapore O-Level Elective History. Detente and the easing of tension in the 1970s, the decline of the Soviet economy, Gorbachev's reforms of glasnost and perestroika, the collapse of communism in Eastern Europe and the fall of the Berlin Wall, and the disintegration of the Soviet Union in 1991.

Generated by Claude Opus 4.86 min readSEAB-2174Updated 2026-06-13

Reviewed by: AI editorial process; not yet individually human-reviewed

Jump to a section

Why this module matters
Easing tension and Soviet reform
Collapse and disintegration
Judging why the Cold War ended
Check your knowledge

Why this module matters

The end of the Cold War closes the O-Level Elective History course, and the syllabus focuses on the decline of the Soviet Union and how it brought the Cold War to a close. This is fertile ground for "how far" essays, for example whether Gorbachev, Soviet economic weakness or Western pressure was most responsible. The skill the module trains is weighing several causes of a great historical change and reaching a justified judgement, the same analytical move you have practised throughout the course.

This guide ties together the module's dot points, each with worked detail and practice. See the subject hub at /sg-o-level/history and the full syllabus list at /sg-o-level/history/syllabus.

Easing tension and Soviet reform

The first two dot points cover the thaw of the 1970s and the reforms that followed.

Detente in the 1970s. Why the superpowers eased tension, the arms-control agreements and improved relations, the limits and breakdown of detente, and how successful it was. Study detente in the 1970s.
Gorbachev and Soviet reform. The problems facing the Soviet Union, the policies of glasnost and perestroika, the new thinking in foreign policy, and how these helped end the Cold War. See Gorbachev and Soviet reform.

Collapse and disintegration

The final two dot points cover the dramatic end of communist power.

The fall of the Berlin Wall and Eastern Europe. Why the Wall was built, why communism collapsed across Eastern Europe, the fall of the Wall in 1989, and its significance. Work through the fall of the Berlin Wall and Eastern Europe.
The collapse of the Soviet Union. The economic and political failures, the effect of Gorbachev's reforms, the rise of nationalism, the failed 1991 coup, and how the break-up ended the Cold War. See the collapse of the Soviet Union.

Judging why the Cold War ended

The set-piece essay asks "how far" Gorbachev was responsible for the end of the Cold War, or for the collapse of Soviet control over Eastern Europe. The strongest answers weigh his role against the deeper economic weakness of the Soviet system and the pressure of the renewed arms race in the 1980s, then decide. Argue that the factors interacted: Soviet weakness made change necessary, Gorbachev's choices made it happen, and Western pressure added to the strain.

Answering "How far" Gorbachev caused the end of Soviet control over Eastern Europe

Take: "Gorbachev was responsible for the collapse of Soviet control over Eastern Europe. How far do you agree?"

step 1: Read the question and plan a stance

The named factor is Gorbachev; "how far" asks you to weigh his role against other causes and decide. Plan a position, for example: Gorbachev's decision not to use force was decisive in 1989, but it released pressures built up by years of economic failure and resentment, so he was the catalyst rather than the sole cause.

step 2: Argue for Gorbachev's responsibility

Explain his role: by signalling that the Soviet Union would no longer use force to prop up the satellite governments, and by pursuing reform and new thinking abroad, Gorbachev removed the fear that had held the Eastern bloc together, allowing the 1989 revolutions to succeed.

step 3: Weigh the other factors

Show the deeper causes. The communist governments were unpopular and the economies were failing, so resentment had built up for years; the Soviet economy could no longer afford to sustain the bloc; and Western pressure and the example of greater freedom added to the strain. Without these, Gorbachev's restraint alone need not have brought collapse.

step 4: Decide and justify

Reach a judgement. A strong answer might argue that Gorbachev was the immediate cause, because his refusal to use force was the trigger, but the underlying economic failure and popular resentment made the collapse possible, so responsibility was shared. The mark lies in the reasoned decision.

The Cold War ended mainly because of the decline of the Soviet Union. Detente eased tension in the 1970s with arms-control agreements but did not end the rivalry, which revived in the 1980s. The Soviet command economy was inefficient and overstretched by military spending and the cost of controlling Eastern Europe. Gorbachev's reforms, glasnost (openness) and perestroika (restructuring), failed to revive the economy and instead loosened control, and his refusal to use force allowed communism to collapse across Eastern Europe in 1989, symbolised by the fall of the Berlin Wall. Nationalism, a failed 1991 coup and continued economic failure then led to the disintegration of the Soviet Union in 1991, ending the Cold War. Essays reward weighing Gorbachev, Soviet weakness and Western pressure and reaching a judgement.

Check your knowledge

Try these under timed conditions, then test yourself with the module quiz.

State what detente was and one of its achievements. (2 marks)
Explain the difference between glasnost and perestroika. (2 marks)
Explain why the Soviet command economy was a long-term cause of the collapse. (3 marks)
State why communism collapsed in Eastern Europe in 1989. (2 marks)
Explain why the fall of the Berlin Wall was so significant. (3 marks)

Sources & how we know this

Singapore-Cambridge GCE O-Level Humanities (Elective History) Syllabus 2174 — Singapore Examinations and Assessment Board (2026)