January 10, 49 B.C.: Caesar crosses the Rubicon and the civil war breaks out. Pompey flees to Greece. At that point, Caesar turns westward and moves against Pompey's allies in Spain, Marseilles, and Africa.

49 B.C.: The siege of Marseilles begins under the leadership of Gaius Trebonius, Caesar's legate. After a months-long siege, the city surrenders to Caesar.

June – August 49 B.C.: Caesar arrives in Spain. A series of conflicts occur in Ilerda, with Caesar emerging as the final victor. Spain is captured by Caesar.

49 B.C.: The legate Gaius Scribonius Curio and Gaius Caninius Rebilus gain control of Sicily. They then cross over to Africa. There, they face Pompey’s legate, Publius Attius Varus, and their ally, King Juba I of Numidia. In the battle at the river Bagrada, Curio is defeated and loses his life.

48 B.C.: Caesar crosses over to Macedonia and clashes with Pompey. In the Battle of Pharsalus on August 9, Caesar decisively wins. Pompey flees to Egypt, where he is assassinated. The victorious Caesar becomes involved in the dynastic disputes of the Ptolemaic kingdom.

In the work De bello Civili, the translation of which is presented in this book, Julius Caesar narrates his victorious wars against Gnaeus Pompey and his allies, up to his definitive triumph and the end of the civil conflict that plagued the Roman state during the years 49 and 48 B.C.