Answer
Gustavus Adolphus was killed in the Battle of Lützen on 16 November 1632. The battle was fought between the Swedish and Saxon armies and the Catholic League army of Albrecht von Wallenstein. Gustavus Adolphus was leading the Swedish army and was killed in the fighting. The battle ended in a Swedish victory, but Gustavus Adolphus' death was a major blow to the Swedish cause in the Thirty Years' War.