Answer:
Napoleon’s empire turned against him.
Step-by-step explanation:
French loss in Russian territory was the first major defeat for Napoleon, a big part of the french empire´s army was killed in that battle and France Allies Prussia and the Austrian Empire turned against them declaring war. The defeat in Russia was a turning point because the French empire was too large to be protected by the weakend army, and that was capitalized by many of the territories that were under french power.