The two countries that most benefited from the Thirty Years' War and emerged strongest from the Treaty of Westphalia in 1648 were France and Sweden. France, under King Louis XIV, was able to gain territory at the expense of the Hapsburgs, and Sweden founded an empire.
The Treaty of Westphalia, which ended the Thirty Years' War, left France larger and more powerful than it had been before the war. It also diminished the holdings of the Bourbon's rivals, the Hapsburgs. Sweden also benefited greatly from the reduction of Hapsburg influence, and the treaty recognized Protestant states' rights to choose their own state religion, which was a positive development for Lutheran Sweden.