The background
The current phase of the war — Russia's full-scale invasion of Ukraine in February 2022 — did not come from nowhere. Relations between Russia and Ukraine have been contested since Ukraine's independence in 1991, with disputes over Crimea, the Russian-speaking populations in eastern Ukraine, gas transit and the question of Ukrainian orientation toward the EU and NATO. Russia annexed Crimea in 2014 and backed separatists in the Donbas region, resulting in a low-level conflict that killed around 14,000 people before 2022.
The 2022 invasion
Russia launched a full-scale invasion on 24 February 2022 from multiple directions: from Belarus toward Kyiv, from the north-east and from the existing front lines in the Donbas and Crimea. The initial assault on Kyiv failed and Russian forces withdrew by early April 2022. The war then became a grinding attritional conflict focused primarily on eastern and southern Ukraine.
The international response
Western countries have provided Ukraine with progressively more capable weapons systems, financial support and intelligence sharing. The conflict has transformed European defence spending: Germany committed to meeting NATO's 2% of GDP target, a significant historical shift.