1. Gaius Julius Caesar : He was a tactical genius …easily defeating Pompey at Pharsalus despite being seriously outnumbered,. also he defeated a much larger Gallic army at Alesia with a masterpiece in siege warfare. effectively conquering Gaul,making him insanely wealthy and powerful.His popularity with the people preventing the republic from ever truly recovering.
2 . Scipio Africanus.: The most important Roman general, if not one of the best.Scipio Africanus literally saved the Roman Republic from being conquered by Carthage. He was just 25 years old when he was commissioned by Rome to defeat the Carthaginians and their leader, Hannibal. At this time, the latter was stationed in Italy, where he had established an almost impenetrable defense, so Scipio attacked Hannibal’s base in Spain, despite a previous failed attempt that had seen both of the Roman Commanders in charge killed. Scipio, however, was successful; he captured the Carthaginian headquarters in Cartagena in 209BC and, a year later, captured Hannibal’s brother, Hasdrubal, by disguising the strength of his forces (hiding heavily armed and armored troops behind a front screen of light infantry). He defeated Hannibal(arguably the best battlefield commander in history) at Battle of Zama- Using Hannibals own tactics against him. The battle ended the 2nd Punic war which basically made Carthage a client state due to the massive repercussions Rome demanded.Scipio retired, never having lost a single battle.
3. Marcus Agrippa: the brilliant general behind the political animal that we call Octavian. Agrippa is responsible for Octavians military victories…His support and excellent battlefield tactics is responsible for winning the final battle of the Republic( Battle of Actium) and pretty much handed Octavian an emperors throne, changing all of history as a result.Also present at victories such as Phillipi and Mutina.
4. Mark Antony: Julius’s Caesars right hand man… needless to say he learned from the best. His tactics mainly helped crush Julius Caesars assassins at Battle of Phillipi- sealing the Roman Republics fate. His brilliant command of the field helped prevent his forces being surrounded at Mutina.. allowing the battle, despite being a tactical defeat, become a strategic victory.
5. Gaius Marius: pretty much made the Roman Republics legions a major fighting force, ensuring Rome to be superpower for centuries to follow.He allowed non-landed Romans to join the army (previously, they’d been required to own property). At the same time, he changed the law so that soldiers had to carry their own equipment (such men became known as “Marius’ Mules”). He also held the elected office of Consul an unprecedented seven times from 107 BCE.Marius also made a name for himself as a General of considerable acumen in several campaigns, especially in Africa and against German tribes. Notoriously, he defeated the Teutones as they advanced into Italy (the tribe had agreed a two-pronged attack on the country with a fellow Germanic tribe, the Cimbri, from their positions in Gaul), ambushing the hordes on the edge of the Alps and killing a 100,000 invaders.