For 10 points, name this 1870 conflict between states led by Napoleon III and Otto von Bismarck.
The losers in this conflict put faith in a machine gun called the mitrailleuse, while the winning side used Krupp steel to improve their field rifles. The losing side in this conflict disastrously split up its army following a defeat at the Battle of Froeschwiller, also called the Battle of Worth. The pivotal battle in this conflict saw a failed attempt to relieve troops under Bazaine by Marshal Patrice (*) Mac-Mahon. Prior to the outbreak of this war, Prince Leopold would have succeeded Isabella II on the throne of Spain. The victor in this war had earlier defeated Austria in the Seven Weeks' War, and this war was sparked by the Ems Telegram. It witnessed the Battle of Sedan and brought down the Second Empire. For 10 points, name this 1870 conflict between states led by Napoleon III and Otto von Bismarck.
The losers in this conflict put faith in a machine gun called the mitrailleuse, while the winning side used Krupp steel to improve their field rifles.
{Franco}-{Prussian} War [or {Franco}-{German} War; accept {1870 War} until mentioned]