What was the turning point for the soviet allowing them to regain power and turn back the germany?

The turning point for the Soviet Army allowing them to regain power and turn back the Germans was the Battle of Stalingrad in 1943. Despite suffering outstanding losses, the Soviet military cut of Germany supply lines resulting in a massive loss of life for the invading soldiers. After this point, the Soviets began to push back the Germans until eventually reaching Berlin towards the tail-end of World War II.