Dissolution of the Soviet Union

Model Diplomat Research Team · Last reviewed June 22, 2026

TL;DR

The 1991 breakup of the USSR into 15 independent states, ending Soviet communist rule and the Cold War's bipolar order.
Which republic declared independence first?
Why did Russia inherit the USSR's UN seat?
What happened to Soviet nuclear weapons?

History & Current AffairsUpdated June 22, 2026

The 1991 breakup of the USSR into 15 independent states, ending Soviet communist rule and the Cold War's bipolar order.

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Timeline

1 December 1991
Ukraine's independence referendum on , in which over 90% voted to leave the USSR.
8 December 1991
The Belavezha Accords, signed on by the leaders of Russia (Boris Yeltsin), Ukraine (Leonid Kravchuk), and Belarus (Stanislau Shushkevich), declaring the USS…
21 December 1991
The Alma-Ata Protocol of , in which eight more republics joined the CIS.
25 December 1991
Gorbachev's resignation on and the lowering of the Soviet flag over the Kremlin; the Supreme Soviet formally voted the USSR out of existence on 26 December.

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On 25 December 1991, Mikhail Gorbachev resigned as Soviet president on live television, and the hammer-and-sickle flag was lowered over the Kremlin for the last time.

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Timeline

1 December 1991

Ukraine's independence referendum on , in which over 90% voted to leave the USSR.

8 December 1991

The Belavezha Accords, signed on by the leaders of Russia (Boris Yeltsin), Ukraine (Leonid Kravchuk), and Belarus (Stanislau Shushkevich), declaring the USS…

21 December 1991

The Alma-Ata Protocol of , in which eight more republics joined the CIS.

25 December 1991

Gorbachev's resignation on and the lowering of the Soviet flag over the Kremlin; the Supreme Soviet formally voted the USSR out of existence on 26 December.

Research it like a delegate

The dissolution of the Soviet Union was the process by which the Union of Soviet Socialist Republics (USSR) ceased to exist as a sovereign state in December 1991, fragmenting into 15 independent post-Soviet republics. It marked the formal end of the Cold War and reshaped the international system from bipolarity toward US-led unipolarity.

The collapse unfolded against a backdrop of economic stagnation, nationalist mobilization in the union republics, and the reform programs of perestroika (restructuring) and glasnost (openness) introduced by General Secretary Mikhail Gorbachev after 1985. The Baltic states pressed early for independence, with Lithuania declaring independence in March 1990, followed by Estonia and Latvia. A March 1991 all-Union referendum showed majority support for a reformed federation, but six republics boycotted it.

Key events in 1991 included:

The August 1991 coup attempt by hardline officials against Gorbachev, which failed within three days and accelerated republican secession.
Ukraine's independence referendum on 1 December 1991, in which over 90% voted to leave the USSR.
The Belavezha Accords, signed on 8 December 1991 by the leaders of Russia (Boris Yeltsin), Ukraine (Leonid Kravchuk), and Belarus (Stanislau Shushkevich), declaring the USSR dissolved and creating the Commonwealth of Independent States (CIS).
The Alma-Ata Protocol of 21 December 1991, in which eight more republics joined the CIS.
Gorbachev's resignation on 25 December 1991 and the lowering of the Soviet flag over the Kremlin; the Supreme Soviet formally voted the USSR out of existence on 26 December.

Russia assumed the USSR's UN Security Council seat and treaty obligations as the continuator state. The dissolution generated enduring issues for international relations, including nuclear inheritance (resolved through the 1994 Budapest Memorandum on security assurances to Ukraine, Belarus, and Kazakhstan), unresolved territorial disputes, and contested questions of post-Soviet sovereignty that remain salient today.

Frequently asked questions

Which republic declared independence first?

Lithuania was the first Soviet republic to declare restoration of independence, on 11 March 1990, followed by Estonia and Latvia.

Why did Russia inherit the USSR's UN seat?

Under the Alma-Ata Protocol and a December 1991 letter from Yeltsin, the other republics agreed Russia would continue the USSR's international legal personality, including its permanent UN Security Council seat.

What happened to Soviet nuclear weapons?

Strategic nuclear arsenals were inherited by Russia, Ukraine, Belarus, and Kazakhstan. The latter three transferred warheads to Russia and acceded to the NPT as non-nuclear states, with security assurances codified in the 1994 Budapest Memorandum.