"Monument to the Battle of the Nations" by mhx is licensed under CC BY-NC-ND 2.0
Battle of Zama (Hannibal)
But after more than a decade in Italy, the Romans had regained their footing and invaded the Carthaginian general's homeland in North Africa.
The fact that Scipio took the honorific 'Africanus' after the battle should tell you everything you need to know about what happened.
The Romans' 35,000 men, aided by a key calvary defection, routed Hannibal's 40,000 Carthaginians.
The Romans imposed harsh terms on the Carthaginians, which never again threatened Rome's growing domination of Europe.
Battle of Leipzig (Napoleon)
By 1813, Napoleon Bonaparte's star was on the wane.
He had invaded Russia the year before with almost 700,000 men.
He had returned from the Russian campaign with perhaps 100,000--losing more than half a million to death, desertion, and surrender.
So in October of 1813, Napoleon found himself with his back against the wall.
He had cobbled together a new army of almost 200,000 men to face off against a coalition force of Germans, Russians, Swedes, and Austrians of roughly the same size.
The ensuing Battle of Leipzig would be the largest battle fought in Europe to that point and would remain so until World War I, more than one hundred years later.
In the battle, the coalition army soundly defeated Napoleon's forces.
Forced to retreat into France, Napoleon would abdicate within a year of the battle.
Battle of Gergovia (Julius Caesar)
Julius Caesar enjoyed living on the edge. Between 58 BCE and 50 BCE, Caesar invaded much of what is now France, Belgium, and England with a relatively small military force.
In what has become known as the Gallic wars, Caesar led roughly 30,000 Roman legionaries and perhaps an additional 30,000 Gallic allies on a meandering path of conquest and destruction.
At first, the Romans picked off tribes one by one, but by 52 BCE, the fiercely independent Gallic tribes had begun to unite around Vercingetorix, a charismatic and competent Gallic general.
At the Battle of Gergovia in 52 BCE, Caesar trapped Vercingetorix and his men atop a hillside near the Loire river in modern-day France.
Yet, the ensuing battle did not go the way Caesar intended.
It's disputed whether Caesar ordered an attack or not, but the Romans attempted to overrun the Gauls who were dug in atop the high ground.
It didn't go well for the Romans.
Caesar reported that he lost 700 legionaries and 46 centurions, but modern estimates place Roman losses in the thousands.
Either way, the Romans were forced to break their siege and retreat.
However, Caesar would get the last laugh when he defeated and captured Vercingetorix later that same year at Alesia.