Battle of Lützen

Though losses were about equally heavy on both sides, the battle was a Protestant victory, but cost the life of one of the most important leaders of the Protestant side, the Swedish King Gustavus Adolphus, which caused the Protestant cause to lose direction. The Imperial field marshal Pappenheim was also fatally wounded.

Strategically, the loss of Gustavus Adolphus meant the French became the dominant power on the "Protestant", or in their case, anti-Habsburg, side, eventually leading to the founding of the League of Heilbronn and the open entry of France into the war.

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