Simplify the following text for a Grade 7 native English-speaking person.
Original: The Battle of Stalingrad was a major battle of World War II in which Nazi Germany and its allies fought the Soviet Union for control of the city of Stalingrad ( now Volgograd ) in southwestern Russia .
Simplified: The Battle of Stalingrad is a battle fought during the Second World War between Nazi Germany and the Soviet Union . They were fighting for control of the city of Stalingrad .