Most Decisive Battles of Roman History

Feb 2017
427
Rock Hill, South Carolina
So I've come up with a list of the 20 most decisive battles of Roman History, and wanted your thoughts:

1. Siege of Veii (396 BC): The Siege of Veii was the retaliation of a string of military defeats that their rival city had inflicted against Rome over the past few years of war. This battle brought the Roman Dictator Camillus to the height of his power and set the city of Rome up as the most powerful city-state in central Italy.

2. The Battle of Trifanum (339 BC): The Romans surprised and defeated the rebelling Latins, badly defeating and dispersing them before a final victory over their remaining forces two years later. Led to Roman domination of both Campania and Central Italy and the dissolution of the Latin League, and Latin cities were turned into Roman colonies. It also set the stage for Roman expansion and domination of Italy.

3. The Battle of Sentinum (295 BC): The height of the Third Samnite War, in which the Etruscans, Umbrians, Senones, and Samnites allied against Rome. In the Battle the Romans led a diversionary force against the Etruscans and Umbrians in their homeland, drawing their forces away, allowing the Roman Army to engage the Samnites and Senones. The Roman victory led to their victories over the Etruscans and Umbrians later in the war and the war itself saw the defeat of all of Rome's major competitors for domination of Italy.

4. The Battle of the Lipari Islands (260 BC): The first real Roman Naval battle, and a defeat, it led to the Romans making a dedicated effort to constructing and maintaining a professional Navy, which allowed them to compete in the mediterranean theatre. They would eventually see victory at the Battles of Mylae and others as a result, allowing them to seize Corsica and Sardinia and most importantly Sicily, resulting in their establishment as a mediterranean power.

5. The Battle of Ibera (Dertosa) (215 BC): Scipio engaged and defeated a large Carthaginian Army under Hasdrubal marching to reinforce Hannibal in Italy through Spain. As a result, the Carthaginians were forced to divert the armies of Hanno and Mago to Spain instead of Italy, resulting in Hannibal operating alone rather than having four large Carthaginian armies in Italy just after Cannae. It was ultimately the deciding battle of the Second Punic War which would lead to Roman domination of Spain and its emergence as the foremost power in Western Civilization.

6. The Battle of Arausio (105 BC): Saw the defeat of a Massive Roman Army, leading to the infamous "Marian Reforms" where Marius changed military recruitment and logistical supply standards, which would be a policy eventually adopted by other senators, leading to the development of the Professional Army. As a result, the Romans also saw a massive increase in civil unrest which led to the Social and Servile Wars of the late Republic.

7. The Battle of the Colline Gate (82 BC): Saw the major clash between Sulla and Marius and set a precedent for years to come. It saw the willingness of Roman forces to fight each other and established a string of powerful Consuls and Dictators exemplified by Caesar and Augustus.

8. The Battle of Actium (31 BC): Octavian, son of Caesar, defeated Mark Antony, allowing him to seize Egypt for Rome which would both fund and supply its armies for centuries to come, and upon his return to Rome he was granted exclusive powers by the senate, setting up the institution of the Princeps, to become the first Roman Emperor.

9. The Battle of Immae (272 AD): At the time Rome was undergoing a crisis similar to that experienced by the Han Dynasty in the Early 3rd Century, where powerful warlords had divided the Empire into their own factions. Zenobia of Palmyra was one of them, who cut off the Roman grain supply by seizing Egypt. Aurelian marched against her once he had obtained sufficient forces and defeated the Palmyrene army at the battle of Immae. This led to the capitulation of most of Syria, the Levant, and Egypt and of course the quick defeat of Palmyra, allowing Aurelian to then turn West and defeat the so-called Gallic Empire at Chalons in 274.

10. The Battle of the Margus (285 AD): Secured Diocletian's accession to Emperor, ending the crisis of the third century. This resulted in Diocletian's stable reign which allowed him to institute or formalize reforms to the government, centralizing the state and beginning the establishment of the Late Roman military system. Ultimately it allowed for a resurgence of Imperial power for the duration of the 4th century known as the Dominate.

11. The Battle of Calama (430 AD): Having exploited the civil war between Constantius Felix and Bonifatius, the Vandals crossed into Africa in 429 AD. Bonifatius, with reinforcements from Aspar caught the Vandals between Carthage and Hippo Regius allegedly near Calama. Bonifatius and Aspar, with the African Field Army and Eastern reinforcements, along with Gothic foederati and bucellarii under Sigisvult, were badly defeated by Gaiseric and forced to retreat to Hippo Regius, which was eventually surrendered to the Vandals. This eventually led to the Sack of Carthage in 439, the fall of Africa and the loss of the West's largest source of income and grain, and the establishment of the first independent barbarian kingdom inside Roman borders. It paved the way for the permanent loss of the west.

12. The Battle of the River Utus (447 AD): Having invade the Balkans, and with the walls of Constantinople undergoing repair, the Romans had no choice but to face Attila by sending three (or possibly four) of their field armies against him. Attila had already annihilated the Danubian defensive system, and met the Romans near the River Utus (Vit?) in modern Bulgaria. Although he took heavy losses, Attila completely annihilated the Roman army, driving the survivors to the Chersonese in South Thrace, where he again defeated the Romans. This allowed for Attila's complete devastation of the Balkans and permanently crippled the Eastern Roman Empire. They were unable to assist the West for the next 20 years, as their military and tax base had been crippled. It also left the Balkans permanently exposed and paved the way for initially Germanic and then en-masse Slavic emigration South of the Danube, allowing for the formation of the modern Balkans.

13. The Battle of Antioch (613 AD): Part of the Byzantine-Sassanian Wars, this was a major Sassanid Victory over the Romans that allowed them to hold on to the recently acquired territory in Armenia, Anatolia, Syria, and the Levant. It prolonged the war by an additional 15 years, and the constant fighting severely weakened both the Romans and the Sassanids. It would lead to dynastic and aristocratic instability in the Sassanid Empire and the crippling of the Eastern Roman defensive system, paving the way for the Arab conquests.

14. The Battle of Yarmouk (636 AD): Truly one of the most decisive battles of world history, after 5-6 days of fighting the Romans were decisively defeated in a major battle against the newly rising Rashidun Caliphate. This allowed their conqeust of the Levant, Syria, Egypt, and North Africa and their decisive conquest of Persia with the defeat of the Sassanids at Ctesiphon. It ended Roman domination of the mediterranean, cut off their two largest tax and grain bases in North Africa and another significant tax base in Syria, and allowed for the worldwide spread of Islam.

15. The Second Siege of Constantinople (717-718): This one actually had worse consequences for Islam than for the Romans. The Umayyads were already at the limits of their power and capabilities, stretched from Spain to Central Asia. The Roman defeat of the Arabs catalyzed the internal turmoil within the Umayyad state eventually leading to its collapse, giving the Romans a major reprieve from Arab raiding and attacks, and allowing them to focus on retaking lost territories in the Balkans. It ultimately ensured the survival of the Empire itself, and arguably Christian Europe.

16. The Battle of Kleidon (1018 AD): The culmination of a series of Wars that had been ongoing for a century between the Romans and Bulgars, it led to the Roman reconquest of the first Bulgarian Empire, and the return of the Romans to a brief height of power after centuries of both external and internal strife due to iconoclasm, succession conflicts, and military catastrophes.

17. The Second Battle of Manitzikert (1071 AD): Although the Battle itself only saw the cessation of Armenian territories near Lake Van to the Turks, it caused a massive internal struggle which led to the breakdown of Roman Anatolia. Seeing opportunity, the Turks then exploited the Roman civil wars in Anatolia to seize most of the region.

18. The Battle of Myriokephalon (1176 AD): Saw the end of the Roman strategic counteroffensive of Manuel II. Although not a significant defeat, it saw the end of offensive campaigning by Manuel II and ultimately prevented the shift in the balance of power that would have allowed for the Roman reconquest of Anatolia.

19. The Sack of Constantinople (1204 AD): It could be argued that this saw the actual end of the Roman Empire, with the dismantling of its central government. However most historians accept it continued as the Nicean rump state and fell in 1453. Nevertheless this reversed the Komnenian reconquests and saw the permanent loss of much of the Balkans and Anatolia for the Romans.

20. The Fall of Constantinople (1453): Widely considered the end of the Roman (or "Byzantine") empire. After almost two months of siege by the Ottomans, they found an unlocked postern gate and entered the city, overwhelming the defenders and killing the last Roman Emperor, ending the Roman Empire.
 
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Aug 2016
29
Sarawak
Where's the Battle of Zama? Cornelius Scipio went against the veteran Hannibal and his veteran army from his italian campaign. There's a lot, really.

Carrhae, Watling Street, Dyrrhachium (1081), Philippi, etc..
 
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Space Shark

Ad Honorem
Mar 2012
3,474
Redneck Country, AKA Texas
Philippi? Teutoburg Forest? Milvian Bridge? Adrianople? The 410 Sack of Rome?

This list seems incomplete for the 20 most decisive Roman battles.
 

Frank81

Ad Honorem
Feb 2010
5,140
Canary Islands-Spain
I miss two particularly:

*Magnesia, 190 BC: the single most successful battle in Roman history. Due to its crushing victory over the Seleucid Empire, Rome destroyed the might of the then considered first world power and deprived it of large territories in Asia. Rome got an inmense amount of money and prestige.

*Adrianople, 378 AC: the defeat and killing of Valens triggered an unstoppable chain of events that led to the destruction of the WRE.
 
Aug 2014
517
Why do you want to know?
5. The Battle of Ibera (Dertosa) (215 BC): Scipio engaged and defeated a large Carthaginian Army under Hasdrubal marching to reinforce Hannibal in Italy through Spain. As a result, the Carthaginians were forced to divert the armies of Hanno and Mago to Spain instead of Italy, resulting in Hannibal operating alone rather than having four large Carthaginian armies in Italy just after Cannae. It was ultimately the deciding battle of the Second Punic War which would lead to Roman domination of Spain and its emergence as the foremost power in Western Civilization.
Good call on Ibera. It's very much underrated in comparison to Metaurus, which typically gets way more attention. However, I disagree with the notion that it was the deciding battle of the Second Punic War and it certainly didn't result in Roman domination of Spain, given that four years later, the Roman armies in Spain were nearly wiped out. Carthaginian power in Spain was only broken after Africanus' decisive victory at Ilipa in 206 BC.

Besides, it's worth remembering that things were still looking pretty rosy for Hannibal in 215 BC. Syracuse and Capua had both defected and Rome was still reeling from it's losses in the previous year. It was by no means assured that Rome would even win the war in Spain after Ibera, never mind the war as a whole.
 
Feb 2017
427
Rock Hill, South Carolina
Adrianople, 378 AC: the defeat and killing of Valens triggered an unstoppable chain of events that led to the destruction of the WRE.
Adrianople? The 410 Sack of Rome?
That's basically a Myth. The Western Roman empire had no involvement in the Battle (the East was waiting for them to send reinforcements). The Visigoths, who would form after the Tervingi and Greuthungi merged with the Goths of Radagasius to sack Rome in 410 AD, would then proceed to suffer a string of Military Defeats against the Romans throughout the course of their entire stay in the empire before finally obtaining the opportunity to expand into Spain in the 460's.

The Goths had a marginal, at best, impact on the decline of the West. Stilicho had far more of an impact on its decline than the Goths ever did, by allowing the usurpation of Constantine III and the crossing of the Rhine because of his obsession with Arcadius.

As a whole, Adrianople had little effect on the Roman Balkans, especially compared to the Battle of the River Utus 50 years later.

Milvian Bridge?
Much like Teutoburg Wald and Adrianople, the Battle is horrendously overrated. Yes Constantine became emperor and Christianity became legal, but as a whole that had very limited impact on Roman history. Christianity would have become legal anyways since it was already dominating a significant portion of the military and aristocracy, and the centralization reforms begun under Diocletian would have been completed by anyone else who had obtained the position, had Constantine not.

Teutoburg Forest?
Had absolutely no impact on history. It's just famous because of the coverage it gets by Roman authors and the fact we've discovered the battlefield location.

Magnesia, 190 BC: the single most successful battle in Roman history. Due to its crushing victory over the Seleucid Empire, Rome destroyed the might of the then considered first world power and deprived it of large territories in Asia. Rome got an inmense amount of money and prestige.
Fair point, it did increase Roman hegemony in Anatolia (and by extension also the Balkans).

Philippi?
I'd really argue Pharsalus if we're gonna pick one of the myriad of battles that took place during Caesar's and the subsequent civil wars.

Watling Street
Again, what impact on Roman history did it actually have? The revolt of Boudicca, much like the Jewish Revolts, are highly overrated. The only potentially serious threat to Roman hegemony was the Illyrian Revolt in 7-9 AD.
 
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johnincornwall

Ad Honorem
Nov 2010
7,803
Cornwall
The aforementioned (another thread) Catalaunian Plains seems sadly missing - being the battle that saved all civilisation !!
 
Mar 2013
1,441
Escandinavia y Mesopotamia
How about Julian the Apostate’s disastrous and foolish campaign in Persia where he decided to siege Ctesiphon without proper siege equipment with that result that the Persian cheated him and let the Tigris River flow, and then hit the crap out of him by wounding him on the retreat?

On his abysmal military preparation and his loss to the Persians, from David Potter’s “ROME IN THE ANCIENT WORLD” on page 287-290:

“In addition to the people of Antioch Julian also seems to have alienated powerful groups within the bureaucracy. Immediately after his occupation of Constantinople at the end of 361, he ordered trials of some of Constantius’s leading official all of which resulted in death sentences(…) It was therefore against a background of considerable tension that Julian launched his attack on Persia in the spring of 363.(…) But he had not brought adequate siege equipment, so there was nothing Julian could do when he arrived in front of Ctesiphon and found that the Persians were unwilling to negotiate and that, as they had flooded the area behind him, he would have to withdraw up the valley of the Tigris.(…) Julian managed to hold his increasingly bedraggled and hungry army together as the Persian army began to launch attacks designed to delay the retreat. Finally, however, on morning of June 26, he was mortally wounded.(…).”


The result? – Armenia was de facto giving to the Persians, and some fortress in Syria/Mesopotamia fell to the Persians east of Dara, and Julian made Roman Empire’s borders weaker in the short time he reigned.



And how about the Battle of Ad Decimum outside Carthage in 533 when the army of Belisarius defeated the Vandalic brothers? – The result was that Carthage fell to the Romans(or Byzantines). Certainly an important and pivotal battle I think.
 
Aug 2015
1,951
Los Angeles
Good call on Ibera. It's very much underrated in comparison to Metaurus, which typically gets way more attention. However, I disagree with the notion that it was the deciding battle of the Second Punic War and it certainly didn't result in Roman domination of Spain, given that four years later, the Roman armies in Spain were nearly wiped out. Carthaginian power in Spain was only broken after Africanus' decisive victory at Ilipa in 206 BC.

Besides, it's worth remembering that things were still looking pretty rosy for Hannibal in 215 BC. Syracuse and Capua had both defected and Rome was still reeling from it's losses in the previous year. It was by no means assured that Rome would even win the war in Spain after Ibera, never mind the war as a whole.
I have to add, that Scipio himself didn't have 100% confidence even after he landed in Africa, hence when Carthaginian senate sued for peace, the treaty suggested (and require senate's approval) was very lenient (compare to the final outcome) and it was only the war party's raid on Roman supplies that was shipwreck and a few other assaults that forced (at least from the Roman's view) Scipio to make an example of Carthage's betrayal of the cease fire.

The Second Punic War wasn't over until Zama, though it was more or less how much influence either side get to keep, since both are too big to knock out in one go in a death struggle.
 
Feb 2017
427
Rock Hill, South Carolina
The aforementioned (another thread) Catalaunian Plains seems sadly missing - being the battle that saved all civilisation !!
A myth by Creasy which is still perpetuated. We don't even know if the Romans won that battle. It certainly didn't "save all of western civilization."

And how about the Battle of Ad Decimum outside Carthage in 533 when the army of Belisarius defeated the Vandalic brothers? – The result was that Carthage fell to the Romans(or Byzantines). Certainly an important and pivotal battle I think.
I'd somewhat say yes because it encouraged the Romans to continue with their reconquest and expend resources. But I honestly think the Justinianic plague was more pivotal than the Gothic Wars, since it killed half the Mediterranean population.

How about Julian the Apostate’s disastrous and foolish campaign in Persia where he decided to siege Ctesiphon without proper siege equipment with that result that the Persian cheated him and let the Tigris River flow, and then hit the crap out of him by wounding him on the retreat?
I didn't include any of the Roman sacks/attempts at Ctesiphon here purely because they didn't actually really play a pivotal role. The Romano-Persian border always fluctuated and the losses under Julian/Jovian were nullified later when the Romans and Persians divided up Armenia. The Roman oriental limes weren't significantly weakened either.

I have to add, that Scipio himself didn't have 100% confidence even after he landed in Africa, hence when Carthaginian senate sued for peace, the treaty suggested (and require senate's approval) was very lenient (compare to the final outcome) and it was only the war party's raid on Roman supplies that was shipwreck and a few other assaults that forced (at least from the Roman's view) Scipio to make an example of Carthage's betrayal of the cease fire.

The Second Punic War wasn't over until Zama, though it was more or less how much influence either side get to keep, since both are too big to knock out in one go in a death struggle.
I see now your point and Publius' point above. Ibera wasn't truly the turning point of the Second Punic War, but I'd argue it was probably the most important battle of the Second Punic War, closely followed by Zama and the Metarus.