Manius Aquillius, probably a son of the Manius Aquillius who was consul in 129 BCE, is a loyal follower of Gaius Marius.

During the election campaign for Marius' fourth consulship, Aquillius had been left in command of the army in case the migrating Cimbri attacked before Marius could return to command the army himself.

As a reward for his loyal services, Gaius Marius runs with Aquillius under a joint ticket for the consulship of 101 BCE.

After the consulship, with Rome struggling with famine caused by the slave revolt on Sicily, Aquillius is sent to put it down.

The revolt of the enslaved on Sicily has nearly managed to subdue the besieged Sicilian cities by starvation, but a second Roman army under the Roman consul Manius Aquillius succeeds in quelling the revolt, only after great effort, in 100; mopping-up operations in the so-called Second Servile War will continue until 99.

This is the second of a series of three slave revolts in the Roman Republic, fueled by the same abuse in Sicily and southern Italy.

Aquilius, having completely subdued Salvius and his insurgents, receives a triumph in Rome in 100 BCE.

Gaius Marius, having gained his sixth term as consul, has meanwhile revised the organization, training, and equipment of Roman armies by the introduction of a volunteer, semiprofessional army, its ranks open to the proletarians or common people.

With the German invaders annihilated (a third horde of barbarians has turned away without troubling Rome), the proletarian soldiers who have accomplished the task clamor for more land, but Rome’s ruling oligarchy refuses to recognize their demands.

Consequently, coalitions begin to form between destitute veterans and ambitious generals.

The popularist tribune Lucius Appuleius Saturninus and the praetor Glaucia propose and pass liberal land laws assigning land in the province of Africa to Marius’s veterans.

However, the radical nature of these bills and the forcible methods Saturninus and Glaucia have used in ensuring their passage alienate a large part of the Roman people.

Metellus Numidicus, now well established as a conservative leader in the Senate, refuses to accept Saturninus' agrarian law, and is consequently exiled from Rome.