Alexandrian war

Caesar attempted to mediate a succession dispute between Cleopatra and Ptolemy XIII and exact repayment of certain Egyptian debts.

[4] Ptolemy XII Auletes' rule was regularly challenged both by domestic rebellion and by other claimants requesting Roman support for their own claims against him.

[2] Auletes attempted to cultivate good relations with Egyptian priests, tried to recentre religious practice around himself as a unifying force, and seek Roman support for his rule.

Cyprus itself was annexed at the initiative of Publius Clodius Pulcher, who appointed Marcus Porcius Cato as proquaestor pro praetore to liquidate the island's wealth, likely to fund a Roman grain project; Auletes' younger brother, who was king there, killed himself in preference to submission.

[3] Driven from his throne and replaced by his daughter, Berenice IV, Auletes travelled to Rome, where he pled his case with Pompey's support.

[a] But after the irregular and contested election of Pompey and Crassus to a joint consulship in 55 BC, the governor of Syria – Aulus Gabinius – received a massive ten thousand talent bribe from Auletes and illegally left his province with his army to overthrow Berenice and install Auletes back to the throne.

When Marcus Calpurnius Bibulus, as governor of Syria, sent his sons as ambassadors to recall the Gabiniani to defend against a possible Parthian counter-invasion in 50 BC, they were killed.

[8] Upon Auletes' death in 51 BC, he left the kingdom to his son and daughter, Ptolemy XIII and Cleopatra (aged ten and seventeen, respectively).

[14] Pothinus, the eunuch serving as regent for Ptolemy XIII, sent secret orders to Achillas to summon his army of some 20,000 men to Alexandria.

Cleopatra smuggled herself into the compound to meet with Caesar, aided by a manservant who rowed her across Alexandria's harbour while hidden in a laundry bag.

Arsinoe escaped and joined the Egyptian army, which proclaimed her queen, and then assassinated Achillas to take control of the force.

Caesar's men then fought a series of small naval battles to maintain control of the harbour and the possibility of resupply thereby.

While Bellum Alexandrinum "gives the impression that... Caesar left Egypt almost immediately", many modern scholars believe he remained there until June or July, possibly holidaying on the Nile with Cleopatra.