Editor’s Note: James Nixey is the director of the Russia-Eurasia Programme at Chatham House, specializing in the relationships between Russia and the other post-Soviet states. He previously worked as an investigative reporter at the Moscow Tribune. The views expressed in this commentary are his own. Read more opinion on CNN.

CNN  — 

On May 9 – known as Victory Day in Russia – President Vladimir Putin will need to make a bombastic and very public display to suggest he is winning the war in Ukraine.

But more than two months in, the war is going far from how Russia originally envisaged. May 9, then, might present Putin the occasion to declare a symbolic “victory” over Ukraine – a great demonstration of patriotic ecstasy aimed at shoring up his manipulated, sanction-weary audience.

The date marks the day Nazi Germany surrendered to Soviet forces (the day after its capitulation to the Western allies, which is why the UK, US and their allies commemorate victory on May 8).

Moscow initially partnered with Nazi Berlin to divide eastern Europe between the two totalitarian regimes. But after that partnership ended with the German invasion of the USSR in 1941, the Soviet human contribution to defeating Germany – backed by enormous shipments of food aid and military equipment from the UK, US and Canada – was critical.

The USSR lost tens of millions of soldiers and civilians in the course of the Second World War – many of them in the then-Soviet republics of Ukraine and Belarus.

Over the entirety of his regime, Soviet-leader Joseph Stalin killed more people both in his own country and in occupied territories than Adolf Hitler. But these days it is a crime in Russia to recall this history, or to compare the atrocities committed by the Soviet Union with those of Nazi Germany. Fresh flowers are still placed on Stalin’s grave in Red Square – where the May 9 victory parade is held.

How important is May 9 to Putin?

Vladimir Putin is an ultra-nationalist who does not believe Russia’s territorial and political ambitions should end at its internationally recogniz​ed boundaries. The countries that used to make up the Soviet Union other than Russia are not considered sovereign by Russia – by most Russians in fact, and especially by Putin.