What was the most decisive battle in history (in terms of historical or strategically impact)?
Conventional books or websites on military history tend to be far too Eurocentric. They also tend to over-weight modern battles, neglecting more important conflicts further back. So I’m going to attempt a more balanced list. I’m going to put them in chronological order, rather than order of importance.
1. The Sack of Carthage, 146BC
With the total destruction of its last major rival, the North African state of Carthage, the Roman Republic achieved total domination of the Mediterranean world.
2. Battle of Carrhae, 53BC.
The Parthians, a Persian Empire, completely destroy a Roman invasion force led by Crassus, who is killed. The destruction of the Roman force marks the end of Roman eastward expansion and ensures that Persia will remain independent as Rome’s most powerful opponent.
3. Battle of the Milvian bridge, 312AD
Under the sign of the Cross, an army of Constantine defeats the army of his rival Maxentius. Constantine becomes emperor, and Christianity becomes officially tolerated in the Roman Empire. Ten years later, it became the official religion of the Roman Empire. The world-altering consequences of this are difficult to over-state.
4. The battle of Yarmouk, 636AD
A Muslim army decisively defeats the Eastern Roman Empire in Palestine. The defeat destroys the power of Rome in the ancient Near East, allowing the Islamic Caliphate to expand across the region with permanent, world-altering consequences. A good candidate for the most significant battle in history.
5. The Mongol Sack of Baghdad, 1258
It has been argued that the destruction of the Abbasid capital, which was possibly the greatest city in the world at the time, inflicted such damage on the Islamic civilisation that it never recovered. The Mongol invasions, which were incredibly destructive and saw huge cities across much of Persia, Iraq and other parts of the Middle East wiped out, played a major role in bringing to a close the Golden Age of Islamic science and enlightenment.