The Romans, from 75, occupy Dobruja (Romanian: Dobrogea), a historical region lying between the lower Danube River and the Black Sea.

Tomis, (modern Constanta) a port city in southeastern Romania, on the Black Sea, settled by Greeks in the seventh century BCE, comes under Roman rule in 72.

Lucullus is wary of being drawn into a direct engagement with Mithridates, due to the latter's superior cavalry, but after several small battles, Lucullus finally defeats him at the Battle of Cabira.

He does not pursue Mithridates immediately, but instead he finishes conquering the kingdom of Pontus and setting the affairs of Asia into order.

His attempts to reform the rapacious Roman administration in Asia make him increasingly unpopular among the powerful publicani back in Rome.

Mithridates, now nearly penniless, has meanwhile been forced to …

…Armenia and the protection of Tigranes.

Crete  had fallen into a pattern of combative city-states, harboring pirates, during the Classical and Hellenistic periods.

Gortyn, …

…Kydonia (Chania) and …

…Lyttos had challenged the primacy of …

…ancient Knossos, preyed upon one another, and invited into their feuds mainland powers like Macedon and its rivals Rhodes and Ptolemaic Egypt, a situation that all but invited Roman interference.

Ierapytna (Ierapetra), a Dorian city in continual rivalry with Praisos, the last Minoan city in the island, had gained supremacy on eastern Crete in the Classical Age.

Hierapytna was later notorious in the third century BCE for its tendency to piracy and had taken part in the Cretan War along with other Cretan cities in the side of Philip V of Macedon against Knossos and Rhodes.

Crete according to Constantine VII Porphyrogenitus was aiding Mithridates VI, king of Pontus, by supplying him with mercenaries in the first century BCE.

Mithridates, intent on halting the advance of Roman hegemony in the Aegean, is at war with the Romans for the third time, and Rome is having a difficult time with him.

The Cretans also contribute to and are in alliance with the pirates of the Mediterranean, which represent a terrible problem at this time; they add the risk of kidnapping to sailing, they pilfer grain from shipments to Rome, and they attack ports.

Marcus Antonius, father of the famous Mark Antony, sends legates to Crete concerning their involvement with Mithridates and the pirates; the Cretans dismiss the matter, and a war begins.

The rebel slaves spend the winter of 73–72 BCE training, arming and equipping their new recruits, and expanding their raiding territory to include the towns of Nola, Nuceria, Thurii and Metapontum.

The victories of the rebel slaves come with a cost: one of their leaders, Oenomaus, is lost—presumably in battle—at some time during these events, and is not mentioned further in the histories.

Many popular modern accounts of the war claim that there was a factional split in the escaped slaves between those under Spartacus, who wished to escape over the Alps to freedom, and those under Crixus, who wished to stay in southern Italy to continue raiding and plundering.

This appears to be an interpretation of events based on the following: the regions that Florus lists as being raided by the rebel slaves include Thurii and Metapontum, which are geographically distant from Nola and Nuceria.

This indicates the existence of two groups: Lucius Gellius Publicola eventually attacked Crixus and a group of some thirty thousand followers who are described as being separate from the main group under Spartacus; Plutarch describes the desire of some of the escaped slaves to plunder Italy, rather than escape over the Alps.

While this factional split is not contradicted by classical sources, there does not seem to be any direct evidence to support it.

In the spring of 72 BCE, the escaped slaves leave their winter encampments and began to move northwards towards Cisalpine Gaul.

The Senate, alarmed by the size of the revolt and the defeat of the praetorian armies of Glaber and Varinius, dispatches a pair of consular legions under the command of Lucius Gellius Publicola and Gnaeus Cornelius Lentulus Clodianus.

Initially, the consular armies are successful.

Gellius engages a group of about thirty thousand slaves, composed of Celts and Germanic tribesmen, under the command of Crixus, near Mount Garganus in Apulia and kills two-thirds of the rebels, including Crixus himself.

At this point in the history, there is a divergence in the classical sources as to the course of events which cannot be reconciled until the entry of Crassus into the war.

The two most comprehensive (extant) histories of the war by Appian and Plutarch detail very different events.

However, neither account directly contradicts the other, but simply reports different events, ignoring some events in the other account, and reporting events that are unique to that account.

The battle between Gellius' legions and Crixus' men was, according to Appia, the beginning of a long and complex series of military maneuvers that almost resulted in the Spartacan forces directly assaulting the city of Rome itself.

After his victory over Crixus, Gellius moved northwards, following the main group of slaves under Spartacus who were heading for Cisalpine Gaul.

The army of Lentulus was deployed to bar Spartacus' path, and the consuls hoped to trap the rebel slaves between them.

Spartacus' army met Lentulus' legion, defeated it, turned, and destroyed Gellius' army, forcing the Roman legions to retreat in disarray.

Appian claims that Spartacus executed some three hundred captured Roman soldiers to avenge the death of Crixus, forcing them to fight each other to the death as gladiators.

Following this victory, Spartacus pushed northwards with his followers (some one hundred and twenty thousand) as fast as he could travel, "having burned all his useless material, killed all his prisoners, and butchered his pack-animals in order to expedite his movement".

The defeated consular armies fell back to Rome to regroup while Spartacus' followers moved northward.

The consuls again engage Spartacus somewhere in the Picenum region, and once again are defeated.

Appian claims that at this point Spartacus changed his intention of marching on Rome—implying this was Spartacus' goal following the confrontation in Picenum—as "he did not consider himself ready as yet for that kind of a fight, as his whole force was not suitably armed, for no city had joined him, but only slaves, deserters, and riffraff", and decides to withdraw into southern Italy once again.