Battle of Waterloo-June 18th, 1815.
This day in history is to thank for the phrase, "to meet their Waterloo," meaning that someone has been dealt a decisive and life altering defeat. For Napoleon, the battle of Waterloo ended his 100 day reign, during which he was able to amass over 72,000 troops to fight Wellington's forces at Mont Saint Jean. *(Fun fact-the actually battle never took place at Waterloo, it was just the location where Wellington's troops were stationed.)
It is heralded as a British victory despite British troops making up only 36% of Wellington's army. The rest were comprised of mostly central European soldiers. It was due to the invaluable contribution of the Prussian army that effectively divided Napoleon's army in two, with neither half able to support the other's attacks. The French army was split between British and Prussian forces and could not retaliate.
The involvement of the Prussians came at the exact right time, as Napoleon had delayed attacking Wellington due to the muddiness of the fields. This gave the Prussians enough time to surround and divide the French army.
The outcome of the battle of Waterloo had enormous consequences that reverberated around the world. As part of the Treaty of Vienna, Britain received territories from France that proved to be integral naval bases in their colonisation of Africa and Asia. America flourished economically during this time due to their thriving export business to Europe as the continent was heavily embroiled in wars. This economic prosperity allowed it to emerge as a global superpower in the twentieth century.
Klein, Christopher, "7 Things You May Not Know About the Battle of Waterloo." Accessed via:http://www.history.com/news/7-things-you-may-not-know-about-the-battle-of-waterloo
John, Tara, "7 Reasons why the Battle of Waterloo is Still Important," Time, June 18 2015. Accessed via: http://time.com/3924075/battle-of-waterloo-importance/