Rather than returning to Rome, Caesar joined the army,

He turned to Marcus Licinius Crassus, one of Rome's richest men. In return for political support in his opposition to the interests of Pompey, Crassus paid some of Caesar's debts and acted as guarantor for others.

While Caesar was in Britain his daughter Julia, Pompey's wife, had died in childbirth

The first Roman republican wars were wars of both expansion and defence, aimed at protecting Rome itself from neighbouring cities and nations and establishing its territory in the region.[123] Initially, Rome's immediate neighbours were either Latin towns and villages,[124] or else tribal Sabines from the Apennine hills beyond. One by one Rome defeated both the persistent Sabines and the local cities that were either under Etruscan control or else Latin towns that had cast off their Etruscan rulers.[125] Rome defeated Latin cities in the Battle of Lake Regillus in 496 BC,[124][126] the Battle of Mons Algidus in 458 BC, the Battle of Corbione in 446 BC,[127][128] the Battle of Aricia,[129] and an Etruscan city in the Battle of the Cremera in 477 BC,[130][131]

During a term as praetor in Iberia (modern Spain), Pompey's contemporary Julius Caesar defeated two local tribes in battle.[187]

Pompey's death did not result in an end to the civil war as Caesar's enemies were manifold and continued to fight on. In 46 BC Caesar lost perhaps as much as a third of his army, but ultimately came back to defeat the Pompeian army of Metellus Scipio in the Battle of Thapsus, after which the Pompeians retreated yet again to Iberia. Caesar then defeated the combined Pompeian forces at the Battle of Munda.