Who lost the Thirty Years' War?

Well, there wasn't really a whole "I won, You lost" result of the war. The Treaty of Westphalia, the treaty that ended the way, has been called the treaty of "Exhaustion" since the nations could no longer fight each other. So no one really lost or won, but if you want to get into the technicalities of it. then Sweden and France won (Sweden being the chief beneficiary of the treaty) as they gained land and left the Holy Roman Empire fragmented again. The reason I say that one won is because no one surrendered. They all just created a peace treaty and Germany had the least amount of leverage.