The Soviet Union lost a total of 26.6 million people, or 13.8% of their 1939 population. Germany suffered tremendously as well of course, with 5.7 million dead, or 8.2% of their 1939 population [0].
This is obviously not a contest, and I'm sure we can all agree that the suffering was tremendous on all sides. However, when it comes to the perception of war in Russia, the fact that the brunt of the Allied war effort in terms of casualties was borne out by the Soviet Union during WW2 (a fact often little known or recognized in Western countries) is especially relevant.