The hastati were frontline, inexperienced infantry troops who led the first charge into battle and were expected to hold the line. If the hastati tired or were struggling to hold the line, they would be reinforced by the more experienced principes. The principes were relatively wealthy Roman soldiers who could afford high quality armor and who were well-trained. In the event that the principes were also unable to hold the line, they would be reinforced by the most experienced members of the Roman army — the triarii.

The armies of the early Roman Republic (prior to the Marian Reforms of 107 BCE) were comprised of a series of different groups, each with different responsibilities and roles on the battlefield. These groups were determined according to class and generally related to the type and quality of armor that an individual could afford. Velites were the poorest members of the Roman military and were generally unable to afford armor. Velites were frontline skirmishers who threw javelins as the hastati advanced upon the enemy.

The Battle of Corinth was fought in 146 BCE between the forces of the Roman Republic and the Achaean League led by the Greek city-state Corinth. It ended in total victory for Rome and the beginning of Roman dominance over Greece.

The Battle of Alesia was the decisive conflict in the Gallic Wars. It was fought in 52 BCE between the forces of the Roman Republic, led by Julius Caesar, and the forces of the Gauls led by Vercingetorix. It ended in victory for the Roman Republic and consolidated Roman control over Gaul.

Vercingetorix was the leader of the Gauls during the waning years of the Gallic Wars. He was decisively defeated at the Battle of Alesia. Vercingetorix was captured and imprisoned for five years before eventually being paraded through the city of Rome in chains and then strangled on Caesar’s orders.

Julius Caesar rose to prominence in the Roman Republic through his conquest of Gaul. After Caesar finished the conquest of Gaul in 50 BCE, he was declared proconsul (governor) of the newly acquired territory. This gave him immense political power and led him to eventually seize power in the city of Rome itself.

The Wars of the Second Triumvirate broke out in the wake of the assassination of Julius Caesar. They were fought between an alliance of Octavian, Mark Antony, and Marcus Lepidus and the forces loyal to Brutus and Cassius. Octavian, Mark Antony, and Marcus Lepidus claimed they were avenging the murder of Julius Caesar, and perhaps that is partially true, but they were really fighting to consolidate their own political power.

Prior to the Gallic Wars, the people of mainland Italy and the city of Rome were under constant threat of barbarian invasions from Gaul. The conquest of Gaul was therefore of immense significance to the Roman people, because it offered them protection and peace of mind. For this reason, Caesar’s conquest of Gaul made him especially popular with the Roman people.

Along with Octavian and Mark Antony, Marcus Lepidus was part of the Second Triumvirate which governed Rome from 43 to 33 BCE. Lepidus tried to consolidate his own power base in Sicily, Gaul, and Iberia, but was outmaneuvered by Octavian. Lepidus’ own troops defected and joined forces with Octavian, effectively stripping Lepidus of any political power. He was driven into exile by Octavian and spent the rest of his life in obscurity.

The Gallic Wars were essentially in Julius Caesar’s rise to power. They were fought from 58 BCE to 50 BCE and ended in Roman conquest of Gaul. The conquest was led by Julius Caesar, and his successes made him immensely popular with the Roman people and the army, and paved the way for his dictatorship beginning in 49 BCE.