On 24 February 2022, Russia invaded Ukraine in a major escalation of the Russo-Ukrainian War, which began in 2014. The invasion has likely resulted in tens of thousands of deaths on both sides and caused Europe's largest refugee crisis since World War II, with around 7.5 million Ukrainians fleeing the country and a third of the population displaced. Russia experienced its greatest emigration since the 1917 October Revolution. The invasion has also caused global food shortages.