480 BC – Battle of Veii (480 BC) – Consuls Marcus Fabius Vibulanus and Gnaeus Manlius Cincinnatus win a heavy battle against Veians and their Etruscan allies. Gnaeus Manlius Cincinnatus and former consul Quintus Fabius are slain.
Battle of Colline Gate (477 BC) – Consul Gaius Horatius Pulvillus has indecisive victory over the Etruscan civilization soon after the Battle of the Temple of Hope.
295 BC – Battle of Sentinum – Romans under Fabius Rullianus and Publius Decimus Mus defeat the Samnites and their Etruscan and Gallic allies, forcing the Etruscans, Gauls, and Umbrians to make peace
Battle of Cape Ecnomus – A Carthaginian fleet under Hamilcar and Hanno is defeated in an attempt to stop a Roman invasion of Africa by Marcus Atilius Regulus.
Battle of Adys – Romans under Regulus defeat the Carthaginians in North Africa
255 BC – Battle of Tunis – Carthaginians under Xanthippus, a Greek mercenary, defeat the Romans under Regulus, who is captured.
251 BC – Battle of Panormus – Carthaginian forces under Hasdrubal are defeated by the Romans under L. Caecilius Metellus.
Battle of Ager Falernus – Avoiding destruction with deceit, Hannibal escapes Fabius' trap in this small skirmish.
216 BC –
Battle of Cannae – Hannibal destroys the main Roman army of Lucius Aemilius Paulus and Publius Terentius Varro in what is considered one of the great masterpieces of the tactical art.
146 BC – Battle of Corinth – Romans under Lucius Mummius defeat the Achaean League forces of Critolaus, who is killed. Corinth is destroyed and Greece comes under direct Roman rule.
87 BC - 86 BC - Siege of Athens and Piraeus - Siege of Athens, which had sided with the Pontic invaders during the First Mithridatic War by Lucius Cornelius Sulla. Roman victory.
49 BC, June – Battle of Ilerda – Caesar's army surround Pompeian forces and cause them to surrender.
49 BC, 24 August – Battle of the Bagradas River – Caesar's general Gaius Curio is defeated in North Africa by the Pompeians under Attius Varus and King Juba I of Numidia. Curio is killed in battle.[2]
48 BC, 10 July – Battle of Dyrrhachium – Caesar barely avoids a catastrophic defeat by Pompey in Macedonia
46 BC, 6 February – Battle of Thapsus – Caesar defeats the Pompeian army of Metellus Scipio in North Africa.
45 BC, 17 March – Battle of Munda – In his last victory, Caesar defeats the Pompeian forces of Titus Labienus and Gnaeus Pompey the Younger in Hispania. Labienus is killed in the battle and the Younger Pompey captured and executed.
47 BC, May – Battle of Zela – Caesar defeats Pharnaces II of Pontus. This is the battle where he famously said Veni, vidi, vici. (I came, I saw, I conquered.)
43 BC, 14 April – Battle of Forum Gallorum – Antony, besieging Caesar's assassin Decimus Brutus in Mutina, defeats the forces of the consul Pansa, who is killed, but is then immediately defeated by the army of the other consul, Hirtius
43 BC, 21 April – Battle of Mutina – Antony is again defeated in battle by Hirtius, who is killed. Although Antony fails to capture Mutina, Decimus Brutus is murdered shortly thereafter.
42 BC, 23 October – Second Battle of Philippi – Brutus's army is decisively defeated by Antony and Octavian. Brutus escapes, but commits suicide soon after.
The Roman Empire under Augustus: The Republic in 31 BC (yellow) and Augustus's conquests (shades of green). Client states are in pink.
Bellum Batonianum (6-9) - An alliance of tribes numbering more than 200,000 people in Illyria rise in rebellion, but are suppressed by Roman legions led by Tiberius and Germanicus.
The Roman Empire under the Tetrarchy, with the territory of Constantius (yellow), Maximian (green), Galerius (pink), and Diocletian (purple)
The Roman Empire in 337, showing the Empire under Constantine (shaded purple) and other Roman dependencies (light purple).
The 4th century begins with civil war resulting in the ascendancy of Constantine I, then, after his death, the progressive Christianization of the empire, and wars with Sassanid Persia and Germanic tribes, punctuated frequently with more civil wars.
363, 29 May – Battle of Ctesiphon – Emperor Julian defeats Shapur II of Persia outside the walls of the Persian capital, but is unable to take the city.
363, June – Battle of Samarra (363) – Julian fights the Sassanids and is subsequently killed in battle. Though indecisive, the battle leads to massive losses for the Roman Empire through a forced peace treaty.
410, 24 August – Sack of Rome – Visigoths under Alaric sack Rome.
413 – Siege of Massilia – Visigoths under Ataulf are defeated by Romans under Bonifacius while trying to siege Roman city. They make peace with Rome soon after.
Roman–Sasanian War of 421–422 - The Eastern Roman Emperor Theodosius II declared war against the Persians and obtained some victories, but in the end, the two powers agreed to sign a peace on the status quo ante.
Late 458 Battle of Arelate -The Roman Emperor Majorian, with the support of Aegidius and Nepotianus, defeats the Visigoths at Arlate. With a treaty, the Visigothic returned all territory in Hispania to the Romans.
461 –Battle of Cartagena – A Vandal fleet surprises and destroys the Roman fleet.
The Eastern Roman emperor Justinian launched an ambitious reconquest of Italy, North Africa and parts of Spain. However, new invaders like the Avars, Lombards and Slavs, alongside the First plague pandemic and various volcanicwinters ended his ambition of recuperate the West and consolidate the reconquest.
589: Franco-Lombard-Byzantine conflict over the Po Valley. The war was stopped by breaching dam in Cucca.
582–602: War against the Avars and Slavs in the Balkans.
By 650 (pictured) the Eastern Roman (Byzantine) empire had lost all its southern provinces, except the Exarchate of Africa, to the Rashidun Caliphate. At the same time the Slavs invaded and settled in the Balkans. The losses continued in the next century
The Eastern Roman empire adopted the Greek language as official language under emperor Heraclius in 610. The Eastern empire shrunk to Greece and Anatolia, because of Persian, Avar and finally Arab invasions.