Dien' Pobiedy:
Today is when Russians celebrate (at least they celebrated it under the Soviets, but I'm sure they still celebrate it now) Dien' Pobiedy, or Victory Day, the victory of course being victory over the Nazis (or, as the Russians say, Fascists). Americans mark V-E day on May 8, but I take it that the surrender on the Russian front happened on the 9th.