The Thirty Years' War (1618-48) was Europe's most destructive conflict prior to the two world wars. Two of European history's greatest generals faced each other at Lutzen in November 1632, mid-way through this terrible war. Neither achieved his objective. Albrecht von Wallenstein withdrew his battered imperial army at nightfall, unaware that his opponent, King Gustavus Adolphus of Sweden, had died a few hours earlier. The indecisive military...