Which country suffered the largest number of military and civilian casualties during World War II?

Soviet Union

The Soviet Union endured the heaviest losses of World War II, with estimates of about 27 million deaths among civilians and military personnel. The Eastern Front was the scene of some of the bloodiest and most devastating battles of the conflict, including the Battle of Stalingrad and the Siege of Leningrad. These enormous sacrifices played a key role in the defeat of Nazi Germany, leaving a lasting legacy of grief and pride in the history of the Soviet Union.