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Russia's invasion of Ukraine
from February 24, 2022 (after Russia annexed Crimea in 2014)· War· Europe
Well documentedSolid records, physical evidence or scientific consensus.
Russia's full-scale invasion of Ukraine from February 24, 2022, Europe's largest war since 1945, eight years after it seized Crimea.
See it on the History map →What happened
In 2014, after protests ousted Ukraine's pro-Russian president, Russia annexed Crimea and backed separatists in the eastern Donbas region. On February 24, 2022, Russian forces invaded from several directions, aiming at Kyiv. Ukraine, led by President Volodymyr Zelensky and armed by Western countries, pushed them back from Kyiv and later from parts of Kharkiv and Kherson regions. Since then it has been a grinding war of drones, artillery and trenches; talks had not produced a lasting peace by mid-2026.
Why it matters
It shattered Europe's post–Cold War security order, drove Finland and Sweden into NATO, spiked energy and food prices, and displaced millions of Ukrainians.
How we know
Satellite imagery, battlefield video, UN human rights monitoring, government statements, and open-source investigators who geolocate footage. Casualties on both sides, likely over a million killed and wounded, are estimates that vary widely.
Still debated
Russia calls it a response to NATO expansion and a defense of Russian speakers; Ukraine and the West call it imperial aggression against a sovereign state. How it ends is unknown.
Connections (2)
▸Collapse of the Soviet Union set the stage for Russia's invasion of UkraineDebated
The connection
Ukraine became independent in 1991 with Crimea and many Russian speakers. Much of Russia's elite never accepted the loss; Putin called the Soviet collapse 'the greatest geopolitical catastrophe' of the century. Disputes over NATO's eastward expansion, Ukraine's turn toward the West and Russian identity grew into the 2014 and 2022 conflicts.
When and how
Ukraine voted for independence on December 1, 1991, with over 90% in favor; Putin's remark came in 2005; Russia annexed Crimea in 2014.
How sure are we?
Putin's speeches and his 2021 essay calling Russians and Ukrainians 'one people' tie the war to the Soviet past.
Debates and open questions
Whether NATO expansion provoked Russia, or Russian imperial ambitions drove the war regardless, is the central and heated debate.
▸Russia's invasion of Ukraine revived tensions reminiscent of the Cold WarMostly agreed
The connection
The invasion revived Cold War patterns: a divided Europe, NATO rearming, nuclear threats, and sanctions cutting Russia off from Western economies. Finland and Sweden ended long neutrality and joined NATO. Russia drew closer to China, Iran and North Korea, which has supplied artillery shells and troops.
When and how
Europe from 2022; Finland joined NATO in April 2023 and Sweden in March 2024; North Korean troops reported in Russia's Kursk region in late 2024.
How sure are we?
NATO records, sanctions lists and defense budgets show the shift; many leaders and analysts use 'new Cold War' language.
Debates and open questions
Whether this is really a new Cold War, given a far more interconnected world economy and China as the main US rival, is debated.