Napoleon III was the emperor of the powerful France. He was emperor until a defeat by the hands of Prussian forces in 1871. How did the French go from almighty to getting kicked around by Prussians? The answer is the Battle of Puebla, in which the United Mexican States scored an victory against French forces in 1862. If the French won the battle, it is likely they would remain a powerful nation.
The United Mexican States are defeated by superior French troops at the Battle of Puebla, which was a pivotal battle in the Second Franco-Mexican War. The greater conflict caused by Napoleon III is known as the Second Napoleonic Wars. The victorious French went on to conquer Mexico and support the Confederate States in the Confederate War of Independence. They recreated the Confederation of the Rhine and put Prussia into economic trouble.