When the Soviet Union ended and the countries that were in it

Russia is still an enormous country, but the Soviet Union was larger still, covering nearly one-sixth of the Earth's land surface.

There are other countries which used to be part of the Soviet Union which are still among the 10 biggest in the world despite now being independent.

But in the early 1990s the Soviet Union ceased to exist, though US President Joe Biden says Russian President Vladimir Putin's aim is to bring it back and that the invasion of Ukraine, which used to be a part of the union, is motivated at least in part by this. Putin was a member of the KGB spy agency during Soviet days, operating throughout eastern Europe. You can follow live updates on the invasion of Ukraine here.

"He has much larger ambitions than Ukraine," said Biden. "He wants to, in fact, re-establish the former Soviet Union. That's what this is about. And I think that his ambitions are completely are contrary to the place where the rest of the world has arrived."

Why did the Soviet Union crumble?

Former Soviet leader Mikhail Gorbachev (Getty Images)

Mikhail Gorbachev became general secretary of the Communist Party, and therefore the leader of the Soviet Union, on March 11, 1985 and aimed to kick-start the dire Soviet economy through reforms (one was known as "perestroika", or restructuring). But these reforms actually led to the state losing control of their previously iron grip on things like the media and the public arena and democratic reform movements grew and gained momentum not only in the Soviet Union but throughout the Eastern bloc where it exerted such influence in countries like Poland, Hungary and the Baltic states. All this took place alongside other significant factors like the collapse of the Soviet economy (a spike in the price of oil helped accelerate this) and its war in Afghanistan.

When did the Soviet Union end as a country?

Mikhail Gorbachev announced the dissolution of the Soviet Union on December 25, 1991. It broke into 15 separate countries. Two years earlier, the Berlin Wall, which split the German city into the democratic west and the Communist east, had been torn down.

Which countries used to be part of the Soviet Union?

A map of the former Soviet Union, with the former republics numbered (they are listed below) (Creative Commons)

The list of former Soviet socialist republics which are now independent states is surprisingly long. And it is not just Biden who believes its restoration is driving Putin's invasion of Ukraine. Putin himself has described the Soviet collapse as the "a major geopolitical disaster", adding: "Tens of millions of our co-citizens and co-patriots found themselves outside Russian territory. Moreover, the epidemic of disintegration infected Russia itself." He is furious that some of these countries are now also in NATO and adamant that Ukraine must not become one of them. This is the full list of countries that used to make up the Soviet Union:

1. Armenia
2. Azerbaijan
3. Belarus
4. Estonia
5. Georgia
6. Kazakhstan
7. Kyrgyzstan
8. Latvia
9. Lithuania
10. Moldova
11. Russia
12. Tajikistan
13. Turkmenistan
14. Ukraine
15. Uzbekistan

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